Remember when I was like “It’s weird that a lot of movies have villains that had trauma that ‘turned them evil’ as a trope”

The thing is, this isn’t even true for Voldemort. By the text of the story, he was just Intrinsically Evil™ and even as a child he was always the one hurting bullying other people and not the one being bullied. So this is one of the worst possible choices of villains they could have used.