alt Hacker NewsThe relevant use case is you come here to see links people share and comment on them. That's sufficiently "social" in this context.
Contrasting the other use case you dabble in (that makes you an outlier) of pulling content from specific sources (I'm going to assume generating original content, not themselves link aggregators, otherwise this topic is moot) via RSS. Most people see that as redundant if they have access to something like HN, or Fark, or Reddit, or Facebook. RSS readers alone, in general, don't let you share your thoughts with other people reading the article, so it's not as popular a tool.
> The relevant use case is you come here to see links people share and comment on them. That's sufficiently "social" in this context.
Just having users submit links that other users can comment on doesn't make it social media. I can't follow particular users or topics, I can't leave myself a note about some user that I've had a positive or negative experience with, I can't ignore someone who I don't want to read, etc. Heck, usernames are so de-emphasized on this site that I almost always forget that they're there.