Fox didn’t create a biased media, which existed long before Fox News did, they responded to it.
Most surveys going back decades and decades show that 80 or 90%+ of journalists are registered Democrats. That doesn’t make them bad journalists, but they are a monoculture that doesn’t represent the diversity of political views in America.
It’s notable how it really bothers people that there is one right-leaning news network out of a dozen or so left-leaning networks. Apparently it’s not enough to control 90% of the media narrative - it has to be 100%.