Social media is very wide term, and arguably RSS is itself social media. There was in fact an overlap between reader users and the intended audience for Google

Social media is very wide term, and arguably RSS is itself social media. There was in fact an overlap between reader users and the intended audience for Google+, lots of bloggers were invited and joined Google+ when it was invite only. I can definitely imagine people using RSS feeds for short portrait mode videos, just as people use RSS feeds for podcasts. Just as we have podcast players to consume this kind of RSS feed, we might have tiktok like apps to consume another kind of RSS feed.