This is just not accurate. Privious to this censorship-push since 1983 there had been a carve out for talks shows and it correspondly has not been enforced since the Regan administration. If it was, Fox News would be in violation 24/7.
Fox News doesn't use public airwaves as I understand it.
Two relevant things: 1. Fox news has a whole network of affiliates who do broadcast. 2. the FCC regulates cable, satillite, telephony and internet in addition to broadcast.