It's called free speech, how about you start valuing it.
free speech is for the commons, it doesnt have to be in your home. People dont seem to get that at all online.
And a public forum where anyone can be a member isn't a commons?
If you want to exercise censorship, feel free to start your own forum.
By definition, an internet forum, with (an) admin(s) and mods, is not a public forum. One person has to pay all the hosting costs, or hosts it himself.