TV rules are weird in the US. This is going to be simplified, but essentially it’s accurate as I understand it. Because of the first amendment guarantees of freedom of speech and freedom of the press, the government can’t actually tell you what you can and can’t say.

Except in the case of broadcast television. Because the way the law works, the right to use those radio signals is owned by the government and granted to companies. So the FCC gets to decide what you can and cannot say on a broadcast television channel.

Fox News is not a broadcast channel, it is a cable channel. So the government doesn’t get to tell them shit and they can get away with whatever they want.