Don't bother with dolts who talk about how bad a given Pope was.
If some Pope had a different personal interpretation of what “Christian Liberty” covers, so what?
The people blathering on about this or that bad Pope all live by Self Alone and the worship of their own, Most High and Holy Self anyway so what they point to as bad behavior today they may say is completely acceptable behavior next week.
After all, nearly all non-Catholics now preach that murdering your own children with contraceptives is no big deal after four hundred plus years of preaching that such murder was sin. Their "Christian Liberty" permits infanticide and whatever else they feel like doing.
The fact is, the worst thing you can say about the Popes they point to is that they behaved like a bunch of Protestants when they knew better than to do so. And even the worst Pope didn't throw out part of the Scripture the way Protestants and Protestant derived folks have.
The same people blathering about the liberties and abuses of papal infallibility have it completely backwards. Infallibility is extremely restricting on a pope because it means he is not free to contradict anything already established ex cathedra. Even in the most flawed individuals who have been popes there is no single example of error in their proclamations. The reason for that is that it is not the pope, but the Paraclete speaking through them. The absolute jealousy of that, like their jealousy of Mary, is what fuels the continued attacks. Pray for them.
Peace be with you