Academic freedom means a rightwing prof can say or teach whatever nutjob theories they want, and also means a leftwing prof can say or teach whatever nutjob theories they want.
Universities are the place where people discuss ideas and it's been this way since ancient Greece. In ancient Greece they didn't have "academic freedom" and Socrates was put to death by the city-state for "corrupting the youth".
Academic freedom is vital because NOBODY, including students or university admin, are the arbiter of what is true. Truth stands on its own merits, because it's either backed by evidence and logic or it isn't. So i say let all the wackjob rightwing and leftwing profs teach whatever they want, because just because they teach it that doesn't mean it's correct.