Reposting my reply from another comment thread on this post

IMO, there have been a few unfortunate unintended side-effects of removing downvotes.

One of them is that controversial posts that would have otherwise gotten a lot of downvotes end up at the top of Active for longer. This is because the Active algorithm sees a post with positive “karma” getting a lot of comments, and puts it higher on Active.

The other effect is that without downvotes, people must reply to posts and comments in order to give any feedback at all. This effect was originally praised as a good thing when the change to get rid of downvotes was first implemented, but I don’t think it’s been entirely constructive. To a certain extent, it’s fostered a culture of dunking and dogpiling, and relies on mods to sort through bad takes instead of letting them get downvoted to oblivion. This effect also creates a sort of feeback loop with the first effect, as controversial posts and comments promoted by the Active sort algorithm tend to get more engagement than they did before, leading to more dunking and dogpiling.

Obviously all of this will need to be weighed with the original issues that caused downvotes to be removed in the first place, but I do like the idea of bringing them back for confirmed non-chuds.