Because we have an entire cult that's caused the deaths of thousands of innocents but they're all getting off with lighter repercussions than a Steven Universe villain. Hell, they're all getting to live happy lives that they don't deserve.
Don't know Steven Universe so that ref is lost on me.
I do know a few stories where villains who has done far worse, one completely ending all life on a world, ended up getting a "happy ending" where she met a hero, trained a hero, fell in love with the hero and now lives as his cat.
I don't particular care if Bel gets lighter repercussions. She's a demon and the demon lord's daughter no less, not exactly an ally of humanity. Not to mention she was an innocent victim to the hero's attack on the demon lord, so if she got some hoo mans killed, welp too damn bad for them. The vampire chick has been reduced to just a living head for now, not exactly a happy life currently (and yet another enemy of humanity). I think the only one who has gotten what you said so far is only Ange. Annnnd that was most likely because she's cute.