[zerocrates]

Just to further clarify, by "mainstream" I meant "the actual test courts use." The "textualist" version is more something to write a law review article about, a theory of how you might get to roughly the same place we are in reality while giving weight to the word "Congress."

Take the state actor doctrine in combination with the fact that the First Amendment is incorporated against the states, and you get the reality that it even applies to, for example, state colleges and universities disciplining students and teachers, despite them not being "Congress," a "law," or even an agent of the federal government at all.