Protected from persecution by the government, which means it has absolutely ZERO relevance to the actions of a private company that has its own right to free speech. They can ban whatever they want! They could say “if you don’t use the oxford comma GTFO” It is their platform. If your solution is to nationalize Twitter, FB etc. then well China is right over there....

Also and because people were apparently deeply failed by their civics classes in HS, “publicly traded” does not mean a company still isn’t private. Private means not owned/run by the state.