I've read once that the middle is not good for speaking the truth. The truth is where the extremes meet. That's ok. But this is a move, it doesn't have to be this way all the time.
You will certainly find more idiots that listen to american pop music in a room than in a room where people listen to classical music. But in my opinion it's not useful to say that people that listen to inferior music are stupid, only because we all know intelligent people who do, including musicians themselves. For example, Ildjarn has already stated he can enjoy any type of music. The guy from Acerbus too, and many other artists that people here like listen to stuff that are shunned here.
That's not for the creators of the site, they already know this really well. It's for the people that may take this music stuff too seriously. A tune is a tune. You either like it or not.
That being said, I agree with the website, and probably most of the smartest people only listen to the good stuff and abhor the bad. And yes, you become what you listen I think, and metal truly is an escape from the karmic cycle while pop music imprisons you more and more on it. Pop music is like schizophrenic voices in your head these days, a mish-mash of infra-human elements that gets people thinking music is whatever combination of words and sounds that feels good when repeating a lot. (baby baby baby, etc.). In comparison with a good pop tune like Aha's Take On Me, you can see how bad a lot of today's songs are.
There are also songs that, composition-wise, are mediocre, but because of their aesthetics becomes interesting, like that new pop song "I am Titanium".