The right wing sees bias in facts, because it's become a non fact-based movement. 

There is much evidence for this, but the "funniest" evidence (tragically funny) was in the last election with the fake news for profit sites. Don't know if you're familiar with the story, but there were/are a bunch of fake news sites being run out of former eastern bloc countries, generating false stories to get clicks and thus ad revenue. In the beginning they targeted both left and right, but after a while they dropped the left because it didn't make them any money. Left wingers are fact-driven, and readily recognize falsehoods, even ones that confirm their own biases. Right wingers? Not so! They clicked, and they shared the fake stories on social media, all day long.