I've seen the guy talking about Sesame Street, and other shows with a liberal bias...he has actual video and audio footage of the writers, producers, etc...talking about specifically wanting to push a liberal agenda....he had proof for all shows he mentioned. NOW, did we the audience every figure it out....on some shows yes, on others, had no clue....but that doesn't mean that the writers and producers did not have the motive, we just didn't see it manifested in the shows that we watched. I mean, I was a little young to be able to see the liberal bias in the Mary Tyler Moore Show, but when you hear the producers and writers talk about what they did, then yeah I can see it.
Also, just because I might have actually seen a bias, didn't mean I enjoyed the show less, but again doesn't mean that the motive was not there.
I mean if they guy wrote a book talking about how "he saw the liberal bias" in all of those shows....then I'd say...meh your opinion, move on. But that is not what he based his book on, he interviewed the writers, producers and actors from these shows for his book and went from there.
I will agree that Fox certainly RAN with the story, putting it on every damn show of theres....I won't buy the book mainly because I'm already tired of hearing about it....I feel like I know what is on every freaking page. I think the only pundit show that didn't talk about it was Greta.