BTW, the existence of the above in itself already disproves the notion. For much of its history, the Church had a tendency to see corruption and abuse everywhere. That is because the entire purpose of the Chuch was to lead souls towards salvation, meaning, Christians had a tendency to see the world as a place where sin and corruption was the default situation. Christ himself told the Apostoles that he had come to call not the righteous, but sinners to repentence. Those that are whole need not a physician, but they that are sick. And since the job of the Church was to heal the sick, Christians had a tendency to specifically look for sickness and sin whenever it could be found.
What many historians today tend to do is just automatically take Christian sources at their word, which would be the equivalent of using medical literature as an historical source. A perfect example is the History of the Franks by Gregory of Tours. This single book is essentially where the modern perception of the middle ages as a place where violence and brutality were commonplace comes from. Even shit like Game of Thrones was based on this single source. Of course, as a Christian, Gregory had a vested interest in trying to focus on everything that was bad in the society of his time. Anybody using this book as a direct historical source without taking this fact into account is falsifying history. The fact many of the horrors and atrocities he was reporting were based on "hearsay" and were likely urban legends in many cases is never taken into account. The fact the horrors he is recounting were intended to "shock" his readers is never considered to be significant for some reason. Many times in the book Gregory specifically refrains from delving too much into the grusesome details of the account he is narrating because, as he says, would be too "disturbing" to recount. Now, if the violence he was narrating was commonplace in his society, how come would he feel the need to censor himself? And in fact, if it was commonplace and seen as "normal", why write about it at all?
And of coruse, missing from the "historical" accounts is the other half of the book, the part where Gregory talks about the miracles and splendors he has seen or heard about, because his book was precisely about juxtaposing the evils and horrors of the world (which he exagerated at every turn) with the splendors and light of salvation brought about by Christianity. So modern historians ignore pretty much everything in the book that has to do with miracles and visions etc (which is literally half the book), then interpret the other half literally while ignoring the intentions of Gregory, resulting in a view of the middle ages that still lingers on today.
And this applies to the history of the Church as a whole, since everywhere you go, Christian literature follows the same theme. The world is nothing but sin and corruption. Abuse and scandal exist everywhere. Everybody using those sources as an "accurate" rapresentation of Church history is of course missing the point entirely. For a society of pure sin and evil doesn't produce saints, and doesn't procude art like this:
Meanwhile, modern art might just be a reflection of the ACTUAL spiritual evil and debauchery of modern times, all of which is brushed under the carpet since unlike the Christians, who at every turn wanted to paint as dire a picture of the world as possible, the modern world does the opposite. It paints a rosy and idyllic picture of what life is today while brushing all the sickness that's rampant under the surface, all of which however finds expression in modern art and the "secret" behaviors of people with their vices and fetishes and so on.