Yes. But, due to powerful cultural influences, humans will tend to want to group together for comfort purposes. Diversity implies fractured culture. Humans are loathe to fracture their sense of community through shared culture.

I'm going with good, fair, and free mass education. All the way to college. If everyone gets the same level of education then no one will FEEL out of place in any culture as they will be aware of common cultural differences through education.

Good education repairs a LOT of social ills.