It's the question you mention that came up for me too: is it possible to cherish someones art if in real life they cross lines? I guess for me the question is what lines. I can separate the art from the person, but whenever the person has explicitly abused someone, ESPECIALLY from a position of power, there is no way back for me. Even Woody Allen whose films I used to like has become a problem for me. And I perfectly understand what you mean by the "purity" being destroyed.
I am rarely touched as deeply by a movie as I have been by CMBYN, it was a very "pure" experience and I fell for Oliver (Armie Hammers), for his body (which is not a big deal as he clearly is very beautiful), but foremostly for his dominant yet caring (?) energy towards Elio. And I don't think anyone can play that, no matter how talented as an actor, if it's not somewhere in their real life. Hence my initial question concerning ttwd.

I developed a crush like a teenager jumping into the world with naive enthusiasm and I feel embarrassed about that. I have calmed down since and told myself that after all it's just a movie and that in real life I wasn't too attracted to AH (as seen in interviews on youtube). Outside of the movie you can sense that something is off with him, whereas Timmy Chalamet (Elio) seems quite charming.

You write:"
Regarding Armie Hammer specifically, I feel his predation exists separate from his kink, so it doesn't taint TTWD for me. There are sickos in every type of sexuality, and their sickness is a thing unto itself, in my opinion. Straight men treat women badly, straight women treat women badly, vanilla types of both sexes treat people badly, etc."

But his marriage apparently was happy and he didn't treat his wife like this. The happily married family man who turns out to be a sick predator on the side. He comes from great privilege and wealth, is blessed with good looks, good schools,is (actually was now) married to a beautiful and smart wife and has two cute kids.

I feel that bdsm (more so than ttwd) might be the perfect playing field for people like him. Much more so than a vanilla context.