Only if God permitted it anyway.  We don't speak of this type of crisis as if it's merely a natural development or progression of historical trends.

As for the moral revolution in the 1960s, it was orchestrated and timed by the same people who brought us Vatican II.  In fact, had Vatican II not happened, the 1960s revolution could not have happened.  It was necessary first to remove the bulwark of the Church against it.  In other words, the 1960s revolution only happened BECAUSE the Church had been taken out (with God's permission).

No, God rightly held that Vatican II was necessary for a purification of Catholics, since the doctrine of the vast majority of Catholics had become corrupt.  Very few Catholics still believed in EENS, and Vatican II was simply a formulation of what most Catholics already believed by then.  It didn't happen in a vacuum and didn't come out of nowhere.  We didn't have widespread orthodoxy one day and then widespread heresy the next.  This heresy was already everywhere, and God permitted it to be formalized by the Vatican II sect so that it could be called out (especially by its fruits) for what it was, rather than to continue subtly and almost imperceptibly (except by a small handful of Feeneyites) to infect the Church.  It was like a cancer infecting the majority of those who called themselves Catholics that did not exhibit any symptoms, as outwardly everything looked fine.  There were many vocations, buildings (churches and schools) going up left and right, conversions.  So no one (except for a few astute individuals) perceived that there was anything wrong.  You see the same kind of thing with cancers.  Sometimes a cancer spreads throughout the body but isn't treated because the individual is unaware that it's there due to lack of symptoms.  But then sometimes the symptoms come out just in time so there could be treatment.  Had the symptoms not manifested themselves, the cancer could have progressed even further to the point that it would have been too late.

God allowed V2 as a course correction for where the Church was subtly headed.

Alas, too many Trad Catholics still think that things were great in the Church through the 1950s.  They couldn't be more mistaken.

So, to answer the question, had God not permitted Vatican II, the corruption of Modernist doctrine would have continued to spread, but God allowed it to help wake some people up, those who became Traditional Catholics.  And yet, we have Traditional Catholics who have not learned the lesson and are falling back asleep.  We see the neo-SSPX slouching back toward Vatican II, and we have the vast majority of Traditional Catholics STILL oblivious to the erroneous and heretical theological developments of the 1950s (and before) regarding ecclesiology and EENs dogma.  We have a similar secondary "awakening" being willed by God, where the arrival of Jorge is waking people up to the problem of Vatican II ... although others are refusing this second wakeup call also.

I can't say that you're wrong, however, for my part, I am not going to try and hazard a guess as to why Vatican II happened.  I've often wondered if it was a misguided, overzealous attempt by John XXIII to try and head off what was prophesied by Our Lady of Fatima in the Third Secret, whatever that might have been.

As to whether the social and cultural revolution of the 1960s and beyond would have happened even if there were no Vatican II, I have to think it would have, I have to doubt whether the pre-Vatican II Church was the katechon keeping all hell from breaking loose.  You had so many things coming together to create the perfect storm, a world emerging from WWII changed in so many radical ways.  You had mass media such as television and rock music emerging, a civil rights movement in the US that was a kettle waiting to boil over, militant atheism in the Communist bloc, raised expectations due to rising prosperity, Catholics just itching to marry non-Catholics and/or practice birth control (my mother told me of a Catholic military wife whose husband was stationed at my father's base, who was complaining about not being able to use birth control, and this was the 1950s), the list goes on.  Again, I have to suspect that even if V2 and the NOM had never happened, somewhere along the line --- it would probably have been when Humanae vitae came out in 1968 --- there would have been at least a mitigated "quiet revolution", people would have said "we're in modern times, we're not doing this anymore", and possibly with the egging-on of liberal Catholics of the Berrigan and John Courtney Murray ilk, they would have either walked away or relegated practice of the Faith to Christmas, Easter, and having their children baptized and making their first communion.  So seen that way, maybe Vatican II, a vernacularized, desacralized Mass, and silence on birth control from both pulpit and confessional, kept people in the pews a bit longer, not saying it was a good thing to compromise the traditional Faith that way, just noting that given these things, the falling-away may have been more gradual and less dramatic.  What we have now, as I'm sure everyone here knows, is a Newchurch where people do what they want to do WRT the Sixth and Ninth Commandments, go to Mass when and if they want to, and receive communion shamelessly while not going to confession.  Newchurch says all is well, it's a new springtime for the Church, and just ignores how rotten it all is.

Where I grew up (Seattle), the Novus Ordo had very little impact.  The archdiocese had already "turned the altar around" and said the Mass in banal English.  I doubt most people even knew, except for a few very small things, that anything had changed.