I think it could go either way. More in my opinion would be better. That means more choice and more likelihood of countries being focused on a singular culture. I really think there is a strong case for voting with your feet and culture is in my opinion a more important factor than current governance systems as a factor for where one should live. People seem to forget this in the US but IMO many of our issues today are primarily due to cultural divides exaggerated by political opportunism. Voting and elections are at best lagging indicators or at worse the result of an easily duped population.

If different cultures can't or won't coexist in the same country why not peacefully spit and just trade with each other. We have done this for many years (trade).