"Fox was the only news outlet in the study that came close to giving Trump positive coverage overall, however, there was variation in the tone of Fox’s coverage depending on the topic."
When you consider this line especially, with everything else, it seems more consistent with "Trump is unusually unpopular and criticized" than "the media is even more liberal now."
Maybe you should think about your own biases here, before continuing to equate "negative towards Trump" with "liberal/left"?
If I wanted to write a post criticizing Trump I'd have an incredibly easy time doing it from several right-wing perspectives: religious/moral, small government/individual freedom, anti-corruption/pro-transparency, take your pick. It's all fish in a barrel.