Lexicus
Deity
What does mainstream media even mean given the audience Fox, Breitbart and conservative talk radio have? It's such a stupid label to put on anything that really is just a shorthand for 'things conservatives don't like'.
In the mouths of many conservatives, I agree that 'mainstream media' sounds a bit silly. Since mindless reaction is pretty mainstream, as Sommer has pointed out.
The "mainstream media" narrative is part and parcel of the romantic underdog delusion. Everyone likes to see themselves as a romantic underdog because it means that they are heroic when they succeed, and excused when they fail, since the odds were against them. One of the ways this plays out with Conservatives is they like to imagine that "the media" is against them, making them romantic underdogs, struggling to get their voices heard against the mighty "liberal mainstream media"... By dubbing it "mainstream" they make the liberals a "Goliath" to their David.
This is true of basically most people who use the term (as quite a bit of 'the left' is also distrustful of the mainstream media but for different and I would argue generally more actually-existing than the reasons conservatives distrust what they call the "mainstream media"). "Mainstream media" is a concept that has validity outside this, though, at least in my view. It's when people use it as a sort of mindless condemnation that it gets silly.