Mainstream media tends to target their audience. Their audience is Americans who by popular vote are left of the government on average, and a higher percentage

Mainstream media tends to target their audience. Their audience is Americans who by popular vote are left of the government on average, and a higher percentage of them that live in cities, which adds to the left bias yet again. So no big surprise that most of the big MSM outlets appear left-leaning if you personally are right of center at all. That doesn't mean Trump is doing a good job.