Government can't ban people from the public square.
Public officials are the government.
Government officials can't ban people from their accounts because that would be the government banning people from speaking out.
Private companies are not the government. They are free to ban whoever they want. They are especially free to ban people that open them up to lawsuits. Government can't force them to allow posts that would get them sued.
Actually ISPs and these types of platforms cannot be sued for allowing defamatory statements to be published on their sites. It's hilarious that FreeSpeech wants that changed. If it DID change, pretty much every single cult member would immediately lose their ability to post, and Trump would be kicked off of every single platform. And most likely those platforms would disappear under an avalanche of law suits against the idiots who constantly post defamatory material.