It means mainstream reviewers have no idea what they are talking about so they can only praise what they think they are expected to praise and people who listen to them play idiotic games therefore learning to believe that idiocy = high quality.
So you believe that all mainstream reviewers have no idea what they're talking about? Interesting that you would lump them all together like that, especially considering that you don't even know them. I don't think someone being mainstream automatically means they're an idiot.