Then I guess you are pretty much the problem here or I should say your ideology is the differing one.

I have been living in Asia for a while, indeed diversity is not seen as anything useful. It's not considered a criteria to be taken into consideration.

I have worked in diverse team and I have worked in a monoethnic team. I haven't seen any difference whatsoever in term of performance.

From my own experience I like working in a monoethnic team. And I like working within a team with a little bit of diversity. But when diversity is going too the roof, then my degree of joy at work start declining.