You raise an interesting question that inspires questions of mine. I don't now the answer, because this is a philosophical struggle, but when is it OK for the government to control what speech occurs on the internet. Not a private entity, but the government. Is it OK to crack down on Iranian propaganda, but not other speech? Is it OK to try to control speech which is too far to the left OR the right? Some people don't want right wing people to discuss things that left wing people believe is demonstrably false. Some people don't want to discuss the role, if any, that race played in the founding of parts of this country's history.
Should the role of government be to restrict the speech of different views? Because both conservatives and progressives seem to want that, but they disagree on what speech is "bad" and what speech is "good."