Is there anything metaphysically inherit to the internet as free speech? That's up for debate. Would the early internet had been successful if this type had not been the ones to build it, I'm on the fence.
The internet simultaneously amplifies speech (this is not new: the printing press did so even more); but, it also concentrates speech. I'm not sure anyone thought about what that latter part would mean.
Like you said, we saw commtech leapfrogging over soctech in the early days of the printing press. But soctech caught up and we got over it. The same exists today - I'm sure we'll develop new soctech to handle it, but I have a desire to hasten that development rather than give up and relying on crumbling/outdated soctech infra in the meantime.
The early internet was full of university staff, large company staff and military. They were mostly professionals and colleagues, and weren't assholes part because you had to be pretty smart and well educated, part because they were watched by their organizations, and part because they had colleagues that could take them to account. If you were an ass, chances were great your victim would easily figure out who to complain to.
There was "censorship", it was just more implicit. The model just started to fail once things got big enough that this model of accountability no longer worked. Systems had to be grafted with various patches to survive the new chaos, such as email, or died off by being spammed and trolled into oblivion like Usenet.
EDIT: I can see some people may not like what I'm saying; but I actively help organize real marches in Texas for orgs like NAACP, AAIA, PPC, etc. We have a stable of lawyers (TCRP, SCSJ, ...); and, I can assure you this is how free speech works in reality.