I mean first of all "great weather and culture", debatable as that is, isn't diversity. Diversity =/= good. It means different. Again I'd debate that the states even has the best weather (what is the best weather anyway?), culture, pay (certainly not from many of the horror stories sometimes told on here, but I guess if your upper middle class theres no need to worry about that), entertainment and food, but that's just subjective.
There's also this idea that europe is just one big country, which it obviously isn't. It's 44 countries, all with very different cultures. I don't really know how you'd define culture, it seems to be very loosely measured, but one easy way of doing so is language, in which europe has 24 official languages, and the states has 1. Switzerland alone has 3 official languages.
I don't hate the states or anything, if you enjoy living there then good for you, but yeh, theres a difference between "I like the culture here" and "here is the worlds greatest culture"