Since you came back and asked nicely i can now address.
I think your example of Tibet, The Yukon, and Peru are misplaced because these are geographical locations where diversity has never existed on the level that it does in the US, and especially in NYC. When you have a city that is comprised of immigrant groups from all over the country, and the world, you have a very diverse population that is reflected in the daily culture (food, art, music, dress, history, etc...) and how the city is shaped/formed. When those same groups are all slowly (or quickly) forced to then leave because of various reasons (affordability, gentrification, etc..) there is a cultural void left, especially when the remaining 1 or 2 groups become the sole influencers of how the city will be shaped from that point forward.
Does that make more sense?