If we consider just Western Europe, I don't see how it is more culturally diverse than the US aside from language.

So what was the last typically Iowan movie?
What's the biggest Texan blockbuster, those days?
Would you say that Narnia 2 is more East-Coast or West-Coast?

Your culture has been in a melting pot for too long.
There might be some cultural micro-exceptions, but your culture is awfuly monolythic in European standards.