Internet residents aren't government. They can't arrest people, lock anyone up, or sentence anyone to death for anything, let alone for saying something. There's nothing there for speech to be free from.
First, the right to freedom of speech only enshrines a right which already existed and which the Founders wanted to ensure would be protected to the greatest extent possible. The free and open exchange of ideas in an open society. Because you cannot have open and honest debate without the free and open exchange of ideas.
Second, we have seen recently that, if someone dares say something that a particular group of people don't like, then they had better prepare to be doxxed, deplatformed, harassed, and for people to harass their employer until they are fired from their job. All while those harassers profess that "freedom of speech doesn't mean freedom from consequences".
Those "consequences" are nothing less than outright intimidation and suppression of the free and open exchange of ideas. And they can be just as damaging as arresting someone and locking them up.
Internet residents can, quite successfully, remove people from the internet and silence their speech on the internet.
Consider Kiwifarms. I am purposefully NOT going to talk about if something is deserved or not. I am not touching that one again. I am tired of it. That said, internet outrage of a minority led to misinformation (both for and against it) and ultimately resulted in the DDOS protection vendor no longer protecting it. Once that was done, to noones surprise, someone ddos'ed it and removed the ability of others to see it.
Its not that internet residents are trying to stop from hearing certain things - in some cases, they are purposefully stopping anyone else from hearing certain things also.
I don't know that I believe this fully but it seems, some days, the internet itself is a country.