HN (and other discussion sites like lwn.net) are way different in this regard. Also, it's not a social medium but a forum. Before social media we had many fora. The success of each of them depended on their specialization and moderation. The more specialized the forum was, the easier it was to keep order because there were fewer trolls. Also the users knew they should not feed the trolls. We hat heated discussions, dramas, long-time users leaving the fora. But practically speaking everything was transparent. Nobody manipulated your "news feed" like they do with FB (an Instagram) to maximize revenue. Nobody suggested to me I should join some fringe groups, repeatedly. Nobody showed to me the stupidities some of my friends wrote on some groups (some of them not even knowing all their friends see it).
Oh of course HN has a ton of problems and problematic solutions (greying out people outside of group think - shouldn't it be the opposite?) but it's way better than FB. Paradoxically, I don't remember when I used HN main page, I'm using alternative interfaces displaying censored posts etc. - one of the many things you can't do with FB.
Of course HN is better than Facebook. It's moderated, limited in discussion topics and the user base skews heavily towards higher educated, older professional types.
It's like being at a professional work event and truly shocked that everyone is well behaved.
