Modern society loves nothing more than a redeemable monster. Those stories can be fun but I kinda wonder if we're in some kind of cultural psychosis about it. I mean I get sexy vampires, but I also didn't need to know WHY Cruella DeVille kills puppies. The woman kills puppies. That should be sufficient reason to not like her.
I think it's partially an outgrowth of folks forgetting how to write compelling heroes. The villains are always more fun (because they don't have to play by rules, duh) and the more heroic a character gets the more "boring" they are perceived as. So if you redeem a villain you get the added benefit of all their backstory making them feel more interesting.
Course, the moment the fun villain starts to be rewritten into someone more cuddly they start becoming less interesting because it's almost never done with any sincere exploration of the implications. It's a lazy device, and so it is inevitably executed in the most lazy way. And usually it's only deployed to wring a few more dollars out of a character that got a lot of heat but who can't, realistically, headline their own story because it would be utterly disgusting to watch otherwise.
"Actually Hannibal Lector eats people because of childhood trauma." No. Hannibal Lector might've had childhood trauma, but he systematically stalks, kills, and
eats people because he's a fucking psychopath.
I find characters like Vader/Anakin, The Grinch, or Scrooge far more interesting in their redemptions because of the moments they have where they realize THEY are wrong. No issues with that whatsoever. It's the things like Cruella or Dracula where they take the character, give them some backstory, and then try to soften up the evils they do (or even try to retcon out that they did anything wrong in the first place) that stick in my craw.
Dracula I'll give just because his transition started earlier as "what if evil was just
sexier"? I'm here for that angle. Still awful, but SEXY awful. Going further to him being a romantic figure takes that further, but at least there's a pathway to it. Cruella is just what I said above. It's a lazy device to wring some more life out of a character that has a good gimmick/look as a villain. See also Book of Boba Fett (which I'll just leave dangling because I could badmouth that show all day long).