There have been many public sinners, many heretics, many usurpers in these last 50 years of the Church, but God still wills that all men be saved.
JPII was a horrible example for a pope, yet as long as he did not despair as Judas did, he would have graces to repent. “Revenge is mine” saith the Lord and it’s not our job to hand out justice. As St Padre Pio often said, this world is full of God's mercy; justice awaits us at death.
Under normal times, JPII (and many others) wouldn’t have been canonized so soon, if ever. But they were, so all we can do is explain to others that them being canonized doesn’t mean they are good examples.