Scripture is replete with statements that "the Church itself could be hijacked by a corrupt hierarchy." All of the major prophets (Isaiah, Jeremias, Ezechias, Daniel), the minor prophets, Jesus's Olivet discourse, 2 Thessalonians 2, the Apocalypse all deal with this reality. In fact the apostasy "in the Holy Place" is the primary subject of all of them, and explicitly so in Daniel 9 and the Olivet Discourse, where the "abomination of desolation" that occurs in the "Holy Place" is discussed.

But let's look at some Papal warnings in this matter:

Pope Paul IV's cuм Ex Apostolatus Officio here:

http://www.dailycatholic.org/cuмexapo.htm [note: you will need to fix the preceding link, because CathInfo uses a regular expression that breaks the URL at the "m" in "cuмexapo.htm." Just replace the strange CI "m" with a regular "m" from your keyboard by typing the URL manually into your browser address bar.]

And Pope Leo XII's St. Michael Prayer, which by the way is included, in original format, on page 1795 of the Angelus Missal. Here is an article about its interesting history and the fundamental change that took place in 1934 (see bolded section below):

History of the Prayer to St. Michael the Archangel

Exactly thirty-three years prior to the great Miracle of the Sun in Fatima, i.e., on October 13, 1884, Pope Leo XIII had a remarkable vision. When the aged Pontiff had finished celebrating Mass in his private Vatican Chapel, attended by a few Cardinals and members of the Vatican staff, he suddenly stopped at the foot of the altar. He stood there as if in a trance, his face pale white, for about 10 minutes before retiring to his office. Shortly thereafter he composed the prayer to St. Michael, with instructions for it to be said after all Low Masses everywhere. When asked what had happened, he explained that, as he was about to leave the foot of the altar, he suddenly heard two voices – one kind and gentle, the other guttural and harsh. They seemed to come from near the tabernacle. As he listened, he heard the guttural voice of Satan tell God that he could destroy the Church if he had 75 – 100 years and greater power and influence “over those who would give themselves over to my service.” God granted this to him, just as He did many millennia ago, granting Satan power over Job.

Fifty years later, in 1934, an important paragraph was curiously removed; around this same time is when the more common abbreviated form began to be used in its stead. Twenty-five years later (75 since the vision), on January 25, 1959, that John XXIII publicly summoned the Second Vatican Council. October 13, 1962 (exactly 78 years later) marked the first working session of the Council. One of the first changes to come from Vatican II, was the deletion of the Leonine Prayers, which included the prayer to St. Michael, in 1964.

The original, complete Prayer to St. Michael the Archangel:

“O Glorious Archangel St. Michael, Prince of the heavenly host, be our defense in the terrible warfare which we carry on against principalities and Powers, against the rulers of this world of darkness, spirits of evil. Come to the aid of man, whom God created immortal, made in his own image and likeness, and redeemed at a great price from the tyranny of the devil. Fight this day the battle of the Lord, together with the holy angels, as already thou hast fought the leader of the proud angels, Lucifer, and his apostate host, who were powerless to resist thee, nor was there place for them any longer in Heaven.

That cruel, that ancient serpent, who is called the devil or Satan, who seduces the whole world, was cast into the abyss with his angels. Behold, this primeval enemy and slayer of men has taken courage. Transformed into an angel of light, he wanders about with all the multitude of wicked spirits, invading the earth in order to blot out the name of God and of his Christ, to seize upon, slay and cast into eternal perdition souls destined for the crown of eternal glory. This wicked dragon pours out, as a most impure flood, the venom of his malice on men of depraved mind and corrupt heart, the spirit of lying, of impiety, of blasphemy, and the pestilent breath of impurity, and of every vice and iniquity.

(The following section in brackets was removed in 1934)
[These most crafty enemies have filled and inebriated with gall and bitterness the Church, the spouse of the immaculate Lamb, and have laid impious hands on her most sacred possessions. In the Holy Place itself, where has been set up the See of the most holy Peter and the Chair of Truth for the light of the world, they have raised the throne of their abominable impiety, with the iniquitous design that when the Pastor has been struck, the sheep may be scattered.]

Arise then, O invincible Prince, bring help against the attacks of the lost spirits to the people of God, and give them the victory. They venerate thee as their protector and Patron; in thee holy Church glories as her defense against the malicious power of hell; to thee has God entrusted the souls of men to be established in heavenly beatitude. Oh, pray to the God of peace that He may put Satan under our feet, so far conquered that he may no longer be able to hold men in captivity and harm the Church. Offer our prayers in the sight of the Most High, so that they may quickly conciliate the mercies of the Lord; and beating down the dragon, the ancient serpent, who is the devil and Satan, do thou again make him captive in the abyss, that he may no longer seduce the nations. Amen. (Ps. 67)

Behold the Cross of the Lord; be scattered ye hostile powers. / The Lion of the tribe of Judah has conquered, the root of David.

Let thy mercies be upon us, O Lord. / As we have hoped in thee.

O Lord, hear my prayer. / And let my cry come unto thee.

Let us pray.  O God, the Father of our Lord Jesus Christ, we call upon thy holy name, and as suppliants we implore thy clemency, that by the intercession of Mary, ever Virgin immaculate and our Mother, and of the glorious Archangel St. Michael, thou wouldst deign to help us against Satan and all other unclean spirits, who wander about the world for the injury of the human race and the ruin of souls. Amen.” ~ Pope Leo XIII

1. In assessing Our duty and the situation now prevailing, We have been weighed upon by the thought that a matter of this kind [i.e. error in respect of the Faith] is so grave and so dangerous that the Roman Pontiff,who is the representative upon earth of God and our God and Lord Jesus Christ, who holds the fulness of power over peoples and kingdoms, who may judge all and be judged by none in this world, may nonetheless be contradicted if he be found to have deviated from the Faith. Remembering also that, where danger is greater, it must more fully and more diligently be counteracted, We have been concerned lest false prophets or others, even if they have only secular jurisdiction, should wretchedly ensnare the souls of the simple, and drag with them into perdition, destruction and damnation countless peoples committed to their care and rule, either in spiritual or in temporal matters; and We have been concerned also lest it may befall Us to see the abomination of desolation, which was spoken of by the prophet Daniel, in the holy place. In view of this, Our desire has been to fulfil our Pastoral duty, insofar as, with the help of God, We are able, so as to arrest the foxes who are occupying themselves in the destruction of the vineyard of the Lord and to keep the wolves from the sheepfolds, lest We seem to be dumb watchdogs that cannot bark and lest We perish with the wicked husbandman and be compared with the hireling.

5. When all this is considered there is good reason to fear lest this great perversity may be as it were a foretaste, and perhaps the beginning of those evils which are reserved for the last days; and that there may be already in the world the “Son of Perdition” of whom the Apostle speaks (II. Thess. ii., 3). Such, in truth, is the audacity and the wrath employed everywhere in persecuting religion, in combating the dogmas of the faith, in brazen effort to uproot and destroy all relations between man and the Divinity! While, on the other hand, and this according to the same apostle is the distinguishing mark of Antichrist, man has with infinite temerity put himself in the place of God, raising himself above all that is called God; in such wise that although he cannot utterly extinguish in himself all knowledge of God, he has contemned God’s majesty and, as it were, made of the universe a temple wherein he himself is to be adored. “He sitteth in the temple of God, showing himself as if he were God” (II. Thess. ii., 2).

https://www.papalencyclicals.net/pius10/p10supre.htm

Fair enough Angelus, but how many of the flock throughout time were actually aware that the Bible warns us that the hierarchy of their Catholic Church could lead them astray and cause them to end up in hell? Was there ever a time in Catholicism when the flock were aware that they had to consider if their pope was giving them true Catholic orders or if he was luring them into error. I certainly didn't, and I was one of millions not familiar with the warnings you posted by popes. Popes warning about these errors, and actually recognising such errors are two different things. The vast majority of the flock has no reason to reject Vatican II for what it really was. It was not until they introduced the NO and Archbishop Lefebvre spoke out did many reralise what was happening. Since then, many thinking members of the flock, such as myself and others that I know, realised what went on and is still going on with Pope Francis. Others, mostly elderly faiothful Catholics do not and think their NO Mass and hierarchy is as Catholic as it ever was as they face their deaths and eternal destination. The Catholic rule that one must be obedient to the pope of the Church was what they followed to the letter. They did not believe they were to personally examine orders from a pope to decide to follow it or not. Surely God will not punish them for doing what they believed was Catholic.

I have so many NO friends who go to daily Mass, monthly confession or more, don't use contraception, say the rosary daily, etc. yet they are falling for the present deception both in the Church and in the world.  

I have so many NO friends who go to daily Mass, monthly confession or more, don't use contraception, say the rosary daily, etc. yet they are falling for the present deception both in the Church and in the world.  They don't like Francis and they are waiting for the Church to be renewed. 

It baffles me how God can allow it, yet I know of course His will is perfect.

1 John 2:19

They went out from us but they were not of us. For if they had been of us, they would no doubt have remained with us: but that they may be manifest, that they are not all of us.

St. Augustine, A Treatise on the Predestination of the Saints, Book II

Chapter 21 - Instances of the Unsearchable Judgments of God.

Therefore, of two infants, equally bound by original sin, why the one is taken and the other left; and of two wicked men of already mature years, why this one should be so called as to follow Him that calleth, while that one is either not called at all, or is not called in such a manner,—the judgments of God are unsearchable. But of two pious men, why to the one should be given perseverance unto the end, and to the other it should not be given, God’s judgments are even more unsearchable. Yet to believers it ought to be a most certain fact that the former is of the predestinated, the latter is not. “For if they had been of us,” says one of the predestinated, who had drunk this secret from the breast of the Lord, “certainly they would have continued with us.”( 1 John ii. 19 . ) What, I ask, is the meaning of, “They were not of us; for if they had been of us, they would certainly have continued with us”? Were not both created by God—both born of Adam—both made from the earth, and given from Him who said, “I have created all breath,”( Isa. lvii. 16 [see LXX.] ) souls of one and the same nature? Lastly, had not both been called, and followed Him that called them? and had not both become, from wicked men, justified men, and both been renewed by the laver of regeneration? But if he were to hear this who beyond all doubt knew what he was saying, he might answer and say: These things are true. In respect of all these things, they were of us. Nevertheless, in respect of a certain other distinction, they were not of us, for if they had been of us, they certainly would have continued with us. What then is this distinction? God’s books lie open, let us not turn away our view; the divine Scripture cries aloud, let us give it a hearing. They were not of them, because they had not been “called according to the purpose;” they had not been chosen in Christ before the foundation of the world; they had not gained a lot in Him; they had not been predestinated according to His purpose who worketh all things. For if they had been this, they would have been of them, and without doubt they would have continued with them.

Augustine, Saint. The Complete Works of St. Augustine: Cross-linked to the Bible and with in-line footnotes (pp. 9456-9457). Kindle Edition.