It's a question of who has access to the internet, and who has the power to influence and set the trends.
Also I get the feeling, that however manipulated the google results are, loads of human beings *DO* spend their time watching teen pop stars and some other not-so-important stuff on telly.
So maybe the aliens wouldn't get such a wrong notion of us little earthlings. And do you know they would use google? Maye the first thing they hear of us is classical epic music, and they would think we're all genius craving for beauty and salvation.
The internet isn't democratic really, but it's still not as manipulated that you could say there is nothing to learn from it.
(With this post I celebrate the fact that after being in this forum for over a year, I accidently discovered there is a place for political discussion and such. Funny how dismissive my brain is, I spent the time "up there" in the Benedict and entertainment section. So, another proof that the aliens wouldn't get it that much wrong. But then again, I'm not confident to take myself as example for a general human being...^^)