They don't have to be nearly that indirect; they are, after all, members of congress. They have broad power to advocate for and pass all sorts of legislation if

They don't have to be nearly that indirect; they are, after all, members of congress. They have broad power to advocate for and pass all sorts of legislation if their demands are not met, to drag C-suite executives in for testimony, and to confer with and oversee executive-branch regulators and bureaucrats. It's often "better" for congress to get "voluntary" cooperation. Not just because it does an end-run around constitutional limits on powers, but also because it launders government action through ostensibly-private actors. Note well that this letter is not addressed to Fox News, but to an important business partner. There's recent history of this strategy, Operation Choke Point did this sort of thing with banks.