I've never appreciated the low-effort handwaves of claiming that HN, old-school Internet forums, USENET, etc. are "social media", simply because they aren't. HN's primary medium is text, often headlined by a link to some other site. That isn't social media. HN makes it quite difficult (technically impossible, but you can link out) to embed media such as videos and pictures, which makes it fundamentally different than "social media".
Many other Internet forums are similar--they might technically have the capability, but the prevailing culture might be that people rarely do it.
Adding to this is that HN has surprisingly little AI-generated content in its discussion threads, and links to AI-generated blog posts, etc. tend to get dogpiled on or simply not upvoted and don't get attention. That makes it fundamentally different from other social media platforms today.
Many other Internet forums are similar--they might technically have the capability, but the prevailing culture might be that people rarely do it.
Adding to this is that HN has surprisingly little AI-generated content in its discussion threads, and links to AI-generated blog posts, etc. tend to get dogpiled on or simply not upvoted and don't get attention. That makes it fundamentally different from other social media platforms today.