CTL,
1. That is exactly my point. They set the limits of discourse. If they do not want an opinion or argument to become known they simply erase it. Sometimes they even cancel people forever. I think that your use of the term “could not” is incorrect. Congress can pass a law declaring social media to be public forums. It just has not. Why would that be a greater threat to democracy than the “equal time” rule? I do think that that there might be strong grounds for an antitrust action when they act in concert, as they did with Parler.
2. A person’s picture certainly changes. Is there a requirement for a picture to have been taken within a certain number of years?