I think having White Diamond redeemed is... maybe a good idea. Maybe because on one hand, it really adds something to one of the major themes of the show (if you make everything perfect, you lose everything that makes you happy), on the other hand there's something about redeeming an abuser (lotsa people forget that Pink, Blue and Yellow are clearly coded to be victims of abuse and White as the abuser) and a multi-planet genocidal murderer and tyrant that's... icky.
It begs the question, does White Diamond even NEED to be redeemed?
Like... come on. Even My Little Pony doesn't go this far to redeem every villain, and it's been running way longer than SU has, with the overall theme of the show being FRIENDSHIP. It at least has Chrysalis that stays a villain, lmao.
If Sugar really wanted to redeem White though, then I'd save her redemption for either the movie or Season 6 (more likely the movie, since I think the reason why Change Your Mind was so rushed was because it was left unclear whether or not SU is getting another season). I think there'd be less discourse if the pacing of White's redemption was a little slower.
Anyway sorry for ranting, this is more of a problem with Change Your Mind than it is with the movie LMAO. I'm still going to watch the show, probably. I like everything else about it.