In the sentence "When it comes to great pop music, It's not about where you are from, but where you are at", what's the meaning of "where you are at"? Does it mean "what stuff are you made of"? or what happens inside you?
It means, more or less, 'what happens inside you' it can mean at what level of understanding you are, what your ideas both culturally and politically are etc.
That 'When it comes to great pop music...' example is misleading, because the 'you' refers to a person; so that phrase can mean 'When it comes to [playing/singing/producing/enjoying/appreciating...] great pop music...'