[bokonist]

The suburbs are isolated because of the decline of the school system. Parents are unwilling to put their kids in schools will they will get harassed and bullied by lower class kids. "Public schooling" results in private communities. It used to be that the richest people in a city would live blocks away from the poor and the working class. That rarely happens anymore because of the association of location with schools.

As for universities - the top universities have a rainbow of skin colors, but the culture is overwhelmingly "Whiter Person" - http://stuffwhitepeoplelike.com/