Again, why the extreme to make a point? No, private companies cannot implement whatever TOS they want. That's why laws exist. There is nothing nefarious about Musk believing that anyone should be able to talk in the public square. He is against garbage hiding behind avatars and pseudonyms spewing nonsense, and he's got a point. It won't be easy to find a solution but I'm pretty he's got a good idea about how to do it.
All this nonsense about his supposed right wing ideas is as bad as the nonsense he received about his left wing ideas with electric vehicles.
Exactly what restrictions do you think exist for a company in creating their own ToS?
I can start a social media platform and say the ToS are I moderate all content and you will be banned if I find your post offensive or insulting other members. Then I decide to ban any posts that have science in them. WHat law stops me from doing this?