There's an asymetry. It's harder to refute a claim than make it. Also who has time to correct someone wrong on the internet for free.

People want to express their reactions. Without an explicit feature, reactions get posted as comments, and these comments are basically spam. You'd get a thoughtful engaging post, and then myriads of spammy "+1", "this", "I agree!!", etc.

I would, however, like to sort by most commented.

I think more explicit features would (positively) transform the conversations. I think all of us that have used Slack have noticed how useful it is to put various Slackmojis on comments at different times... Seeing "+1", "1000%", ":questionmark:", ":thumbsdown:", etc on a comment doesn't detract from the comment, nor elevate it, but it does show you what people think.

Similarly, HN could have 'reacts' that express a psychological or emotional state, or an opinion, or quality. Slashdot has forever had moderation points that have qualifiers like "Funny", "Insightful", "Flamebait", etc. This tells you why something has the points it has, which can lessen the emotional panic and internal threat you experience when you get downvoted to hell, or enhance a feeling when you get upvoted. This, on a large scale, changes how people act, by allowing them to receive and give qualitative comment feedback.

And it should be trivial to add sorting/filtering of any of those things. (That's another feature Slashdot has since forever... you can hide comments below a threshold of points)

(And yes, Slashdot is a tire fire of a "community", it's just the example that comes to mind. GitHub comments also have reacts!)

Yes I support these features as well. Reactions work well to gauge popularity, interest, morale. And makes for a less cluttered interface as well.