It's probably companies advertising their products getting salty their new movie or something got 90% downvotes and YT is all too eager to please its ad overlords.
It started when a Joe Biden speech video got disliked into oblivion. We're talking 2 million+ dislikes.
Why not do things transparently and do weighting by default weight = upvotes - downvote + us cents paid by author, all 3 visible.