That has nothing to do with the policies of the region, and everything to do with the volume of taxing oil operations work that requires limited/no education and can pay 6 figures.
That largely comes down to out-of-control housing cost, which does owe to policy. Can't move up if you can't move in to where the economic growth is.
One of the motivation behind NIMBY is to maintain high property values and most of all keep out multi family housing in order to price out the lower classes. This results in huge differences in k-12 educational quality and thus opportunity, due to school zoning.
You're mischaracterizing typical NIMBY motivations. When I talk to those people they are mostly long term residents who are more concerned with quality of life issues like noise and traffic. They don't care as much about property values because they aren't planning to sell; they expect to die in their current homes. And they oppose new development even in cases where it would increase their own property values.
Economic mobility is not the be-all and end-all of statistics: in particular, if everyone's income exactly doubles (and prices stay the same), then during that interval (the doubling) there was zero economic mobility.