Honesty, I don’t think I really like upvotes and downvotes at all. My favorite system is Discourse where the only sort option is old -> new and you can provide reactions (heart, thumbs up, etc…) that don’t change the sort at all. This lets you follow the discussion as it happened & gauge engagement yourself.
I don’t know the full story but a lot of Lemmy devs/early adapters were Marxist-Leninists who kind of got drowned out by the more liberal Reddit users. I was a (very) passive lurker for a while so I only know a little bit of the story, namely that Lemmy used to be a lot further left. Someone who has been more engaged back then would be more helpful than I.