Yes, it is an extremely dangerous power. It is also, unfortunately, sometimes necessary, especially in emergencies. I'm generally strongly opposed to eminent domain when it's used for "economic development" and other such goals, but COVID was a textbook example where it was warranted.

And as for the difference between "speech" and "action", what the released emails show is that the government didn't stop at speech - it used Twitter as a proxy for censorship, and censorship is an action.