Mumble? Teamspeak? It's like everyone forgot the old battle-tested Warhorses.

I think IRC (which OP mentioned) outranks them all ifor the battle tested warhorse title

As if an IRC channel wouldn't be shut down if it threatened oligopoly profits...

All of the big social media networks are corporate property. It is not a public space. So it is their house rules. And rightfully so. If you took their free cookie, choke on it, but don't complain.

Wow, that's aggressive.

All journalists, nearly all politicians, and lots of other people as well communicate largely on social networks owned by these giant amoral artificial creations. What does "public space" even mean anymore? Should we stand on the stroad median with the panhandlers? Would anyone even read our signs?

It is possible for citizens to impose conditions on the existence of the corporations their elected government creates.

Except when people do create their own shit, like Parler, it immedietly gets shut down as soon as it gets popular.