By default, Lemmy allows downvotes globally. However, when a server disables downvoting, it is similar to using a feature that is usually reserved for enterprises and very small, non-federated communities.
If a user prefer to not see downvotes, they can disable it by his favourite client settings, but the rest of the community should not miss this functionality for the pleasure of few users.
Disagree, the downvoters would just pick a default reason and move on… maybe even turning one of the reasons into a troll motive.
Remember we’re talking about people who only care enough to go out of their way to mass downvote or even have scripts to do it for them; not normal users who up/down vote and move on (which weren’t the problem back then, as far as we were told).
Forcing a reason maybe would stop people who actually cared enough, for the rest it would just be a nuisance so they’d pick whatever (or the meanest option).
Honestly… after reading another guy’s comment, I am more inclined to just say fuck it and say we return to the forums, no upvotes or downvotes, things neatly categorized into their place (specially so sensible things can be hidden but still available) and if someone wants to interact they’d have to comment.