I’m an old age redditor, and that was may reddiquette, “don’t downvote just because you don’t like the topic, maybe other people find it interesting”.
Mostly I don’t downvote at all, only on some rude or spam posts.
Reddit just become something where everyone downvote everything for no reason, even if just say “OK” ou “that’s cool”!
On Lemmy (ate least for now), not so much or I don’t see it.
If you see a post “orange is the best color”, don’t downvote just because you don’t like orange, leave a comment and express your opinion instead
PS: There’s an old Reddiquette song, the same can be applied to fediverse
https://youtu.be/4fLpktf2jYw
Obtainium https://github.com/ImranR98/Obtainium