If MSNBC and CNN are mainstream media what is Fox News? It is main stream media as well if those two are.
The contention that there is a main stream media bias against all conservative thought completely ignores the power of the the Wall Street Journal, FOX News and all its affiliated media entities, the myriad of weekly publications and online conservative media.
It doesn't make one a liberal, conservative or independent to be concerned about the online foreign government influenced messages in social media and the like. I'd worry about the falsely cloaked foreign government infiltration more than the perceived bias of the so called main stream media. Sarah Palin has ridden the fallacy of the MSM bias into the ground already.
Most importantly, Trump, Bush and Reagan are proof positive that IF their is a MSM and IF it is biased, then the minds of the people are not controlled by such. In the past 35 years how many years has the Congress been liberal versus conservative (Dem v. Rep)? How many state governors are Democrats versus Republicans? How many state legislatures are Republican versus Democratic? If the so called MSM is biased then it is very ineffective and unlikely to become effective any time soon. Seriously, there is a MSM possessing a big powerful influence? Hardly.
The MSM fallacy is all about political victim-hood which helps win support every political season.