Yes. It is. Isolation inherently breeds tribalism, prejudice, and fear of the other. It is extremely harmful.
It depends. If we think about Middle-Eastern and Balkan stuff, physical separation may really be better than mixed living which may turn into a mutual slaughter any day. That would be because cultural isolation doesn’t require physical separation, and other things.
If we think about poorer and richer layers of the same general culture, with the poorer layers having more people with African ancestry - then yes.
It depends. If we think about Middle-Eastern and Balkan stuff, physical separation may really be better than mixed living which may turn into a mutual slaughter any day. That would be because cultural isolation doesn’t require physical separation, and other things.
If we think about poorer and richer layers of the same general culture, with the poorer layers having more people with African ancestry - then yes.