with the caveat that I think this should only apply to social media in the strong sense of that term, that is platforms where you present with an identity and that function as public squares, you having any rights is conditional on you being a citizen in the first place.

Given the country in question, if you lived in a Greek polis participating in democratic debate required you to share the same national identity, anonymous-guy#500 from the polis down the street never had any rights to participate. That's not mob rule but the opposite. It's precisely in the mob where anonymity facilitates violence.