Honest answer, not something we’ve achieved yet. Some hints of it in NNTP, HTTP, RSS/Atom, Usenet… but until we decide that Internet connectivity is a fundamental human right and actually back that up I think we’ll still be a long way off from a digital commons.
Mastodon, Lemmy, any other Fediverse project.
Sure you could argue that any individual server is privately owned, but the collective protocol is about as public as something like social media can be
When did a protocol became social media (in a common sense)? I may have missed something.