The way I read the landscape, POTUS is free to tell anyone to do anything, and everyone is free to tell him to go **** off.
He can TRY to coerce, intimidate, "enforce", but people will start screaming if he goes too far. (Which he has).
The PROBLEM in this equation, is that the Zuckerbergs of the world, DON'T tell him to go **** off.
That's a pretty serious problem, if you're a student of history. The economic system called fascism is DEFINED by the nexus between the corporations and the state.
The problem is, the corporations become part of enforcement. POLITICAL enforcement, not legal enforcement. For example, Zuckerberg seems to think his job is to "suppress misinformation", which is a purely political concept with a political goal and a political agenda.
If THAT goes too far the Boards of Directors can start screaming, but first of all they may or may not (scream), and secondly even if they do it may be too late.