You and I have different definitions of public space.
I've been on the net since the early 90s, and even back then there were no public spaces.
There is nowhere online, and really never has been, where you have a right to be, or where you can express your government-given rights (also, which government? most of us are not US citizens) without anyone having the ability to cut you off or kick you out at their own discretion.
Every server, whether it was Usenet, IRC, the web, email, or otherwise, was, and is, owned by a private entity that could moderate, manage and restrict usage as they see fit.
If you cause them enough trouble, they will boot you, and have every right to do so.
