None of this happen because "they are strangers in their own land" (which is just a cowardly way to complain about brown people).

This happen due to economic pressures and incentives. The neighborhoods are closed off because it became too expensive. Stores and restaurants disappear when rents gone up and most people prefer to buy shit on Amazon or use delivery apps for food.

I have no fucking idea what you are talking about children being excluded from playdates.

Rejected employment "in favor of the one of the tribe" is plain bullshit.