My instance has downvoting enabled, but I’ve learned that some other instances do not. Do the vote totals look different to users on different instances? It seems like some users on instances that don’t allow downvoting are unaware that it’s not the same lemmy-wide. It would be pretty confusing for them to see their vote go down.
I see your points, and they do make sense, but I respectfully disagree with your conclusion. My reasoning is that, from my experience, a downvote has no nuance. A reply saying “this is wrong and here’s why” with a hundred upvotes is useful. A downvote is basically the equivalent of flicking a peanut.
The thing is that people usually won’t take the time to write that reply and in case of trolls, they shouldn’t be wasting their time.
YouTube’s dislikes used to be great for telling useful content apart from useless spam at a glance without even clicking on it. They removed them, so now we have to read the comments before watching a video if we want to avoid wasting time.
In this day and age, information flows so fast there isn’t always time for nuance. The downvote isn’t perfect and misused often, but it does serve a purpose.