> My own reason is .. maybe not possible to hit on research papers.

I think fancy people with appropriate credentials and .edu emails are all using openreview? So the audience is what, the unwashed masses who also happen to be doing some light reading at the bleeding edge of knowledge? Surely there are dozens of us I tell you, dozens! =P But yeah, maybe not enough to sustain a social network.

Never heard of alphaxiv, will try. I would also love for this to work, probably not willing to risk slogging through science twitter/bluesky/mastodon. Honestly HN would be the obvious place if it would add a pretty simple tagging system as most of the people interested are probably already here. I don't think we'll see that, because if we had filters no one would go to the front page, and that'd be a bad thing for certain interests.