Small observation on this great comment :)
I noticed on twitter that the culture (at least in my bubble) valued „smartness“ over empathy. In attempt to say something „smart“ it lead to many snarky responses.
I also noticed this pattern in myself, which is why I stopped replying to tweets. (It was easier for me to stop replying than stopping to reply in a snarky way).
For twitter I think this is not only a question of community, but also a question of design (ui/ux). And how the ui/ux shapes the community.
If I ran HN, I would consider if there are any (small) UX changes in the comment flow that could improve the „well, actually“/contrarian metric.