That's because the left is spread among more outlets. MSNBC, CNN, NYTimes, NPR. Whereas Fox is the only major media outlet for the right.

You can see the partisan breakdown here:

https://www.pewresearch.org/fact-tank/2020/04/01/americans-m...

Also you can find many "blue checks" and their followers on Twitter who take MSNBC as scripture to a frightening degree.