They should've gone deeper into Joan Crawford's psyche

There's alot of speculation that this depiction of Crawford is a gross exaggeration of who she truly was, and few people, if any, have ever vouched that she was actually this evil outside of her daughter Christina. If that's the case, they should've explored Crawford's psychological torment.

The entire movie, I saw a woman that was clearly broken and suffering from an extreme mental disorder. Because of this, I found it hard to just label her as this one-note villain and I think the director's decision to make her such is kinda disgusting. Not condoning these (fake) scenarios, but she's obviously suffering from an extremely bad mental episode during the wire hanger scene, likely caused by childhood abuse, or unfixed trauma, or schizophrenia, or SOMETHING. Why not explore that? Was it really that difficult in 1981 to see when someone was mentally broken? Is it that hard today? I think diving into her psyche would've made things WAY more intriguing.

If they wanted to go the "Joan is pure evil" route, they should've made her appear calm and outgoing on the outside, a woman who only becomes a tyrannical abuser behind the scenes when nobody is around. This would make Christina's claims feel more believable and would help the audience feel utterly helpless. Instead, the filmmakers make Crawford into a cartoony villain who is explosive and abusive 24/7 to everyone around her, which is unrealistic because NOBODY would've ever put up with that. I know she was odd and hard to work with but I doubt she ever would've become a mainstream celebrity if she were that evil to everyone around her like she is in the movie. It would have been WAY creepier had she appeared charitable in public, and Christina is the one who thinks she might be going crazy because nobody believes her claims.