I think Moldbug's main point is that even if cynical people acknowledge that the media often uses its powers in biased ways, there's still an ideal that the media should be this fair and balanced impartial observer that just provides information and then lets the people decide. Moldbug beleives such an ideal to be naive and unworkable: the media will allways be biased, and will always use its powers to influence the secular political enviroment, and expecting it not to grossly misunderstands what the media actually is, how it operates and what its incentives are.

There's also the fact that when people think of "biased" media, their minds tend to jump immediately to media that is biased against their own political views, while being blind to the biases of their own favorite media source (witness all the liberals, who rightly decry Fox News while putting NPR on a pedastal).