There are a number of issues, but probably the biggest is the spectacular refusal of the bishops and priests to teach, or model, the Catholic faith to the people. In particular is my RCIA instructor who rejected the Trinity, taught us Muslim prayers (in front of the priest) and said we really have no way of knowing what happened with “the Jesus events” because the records are untrustworthy and were written centuries after those events. He thought there was no way we could know if someone named Jesus ever lived. He is the director of religious instruction. I looked at the parish paper recently and he wrote an article in which he discussed Jesus having demons in him.
I heard a homily once on how to make bread, another on the places in the sanctuary where the bishop anointed the place.
I have repeatedly run into Catholics who know much less about Catholicism than I do, even on CAF, and Catholics who, by their lifestyle, testify that the Church is not to be believed. In our church we have many people who have left the Catholic church and repeatedly say that the reason they left was the lack of teaching. I know a woman who went to parish school with the children of the mafia - everyone knew what the parents did - but it was ok, there was no call for repentance or holy living. One could be a good Catholic and be in the mafia, too. That’s what she grew up with. Another woman I know said what she likes about being a practicing Catholic is that there is a loophole for everything, so you can do whatever you want without ever worrying about sin. This is the testimony of Catholics I know, and CAF is a small voice in a roaring river of this kind of stuff.