I wouldn't classify Hacker News as 'social media' per se.

Hacker News does not have the feed-driven approach of other social media that is designed to generate addiction/engagement amongst users; we just like to talk about fun stuff. Hacker News is more of an old-school forum, where we talk about topics, rather than being a true 'social media' experience where you can talk about anything/yourself as a topic.

Moreover, the average baseline of discussions here is much higher and more intellectually-driven than discussions on X, IG, FB, and so on. That makes it keenly distinct from other social media designed for more base discussions.