But that's not the case now. The platforms hosting your work are privately owned, the large community websites/social networks/whatever with millions or billions of users are privately owned, and a larger portion of real life locations people frequent are privately owned too.
The way society is going seems to be making the amendment less and less relevant as time goes on.
Exactly. As society moves more and more online, it moves more and more into a virtual territory that is owned at every level by corporate entities who grant no rights to their users. If we're not careful, we could end up with a strange cyber-feudal arrangement.
The "it's their platform" argument seems strange to me when you start getting into the question of corporations beyond a certain size or monopoly. In the 1700s I'm sure there was a lot of arguing that certain kinds of protest were groundless because this is "the King's land." It took a re-examination of what the boundaries should be before that changed.
It was certainly much more expensive to distribute writing in 1800 than it is today. It would be much easier to stop a person from printing.
Exactly this. When the First Amendment was authored, I don't think it was even conceivable that any organization besides a government or state church could effectively censor speech at scale. Now that we have "private" organizations that effectively have that power, it's perhaps time that the law be updated to reflect that change in facts and preserve people's right to free expression.
The internet shouldn't be another Zuccotti Park.