The greatest trick the GOP have pulled is creating/reinforcing the victim mentality among it's support. Part of that is the idea that the "mainstream media" is full of liberal elitists out to screw out the good ol Real American®. It's bullshit. Fox News is, by far, the most watched cable news channel every day. The Sinclair Broadcasting Company is strongly conservative and has local news coverage in something like 70%+ of markets. Papers like the Wall Street Journal and NY Post are among the highest circulated in the country.
Ultimately, the media make mistakes and are too often driven by clicks/ratings. But that's been true for a long time.
If you think NYT/CNN are biased, what do you think of the blatant lies by the likes of Trump, Fox, Breitbart, etc every single day?