I think it is a mistake, although a reparable one, to treat our artists and our entertainers as if they need to be moral paragons.
By this I don't mean that we should look the other way when one of them does something terrible. What I mean is we need to have more nuanced ways of taking what matters for us from a given creator and from their works. It does us no good to hold them to standards that they can never meet in the first place, just as it does us no good to pointedly ignore their failings and say, "I'm only here for the art."
My own dividing line for "enjoy the art, the hell with the person" is probably whether or not the person in question can monetize my attention. If they're dead, they can't do that, so that means all of the artists of previous generations who no longer collect royalties on their work are fair game. I don't plan to ever watch another Woody Allen movie; the toxicity swirling around him and his creation at this point is too much for me to sniff the fumes of, let alone swallow.
But I also don't plan to use that as a way to make excuses for their excesses. I still think Wagner was a wretched human being, albeit one who had a body of work worth learning from. But if you don't think you can set aside all that sickens you about the man, even if he is long dead, then I don't blame you. We can always find other inspirations. Deep ocean, vast sea, plenty of fish in them to choose from.