That's irrelevant. It all comes down to ownership and audience. The Daily Mail is the most right wing rag going in the UK, but not all its journos are equally right wing.
Reagan made the change by allowing broadcast news to say what it wants with scant regard for the truth. That allowed Fox to make stuff up and the others meekly followed suit.
In the run up to the illegal invasion of Iraq the only news organisation that didn't broadcast Whitehouse propaganda was PBS. That's pretty right wing.
I know you don't care about the BBC, but it's not allowed to do that. It's obliged to broadcast the truth without political bias. That's why it's trusted throughout the World, unlike American Media. During the Cold War dissidents behind the iron curtain weren't listening to Radio Free Europe to find out the truth, it was the BBC.
Yet American news organisations call the BBC left wing. It's no such thing, by act of parliament. So going from the position that anything to the right of the BBC is right wing we have a right wing Media and a far right wing Fox in America.
Fox have proved that if you repeat a lie enough times people will believe it. You do.