I am not so sure on that. They raise inflation, home prices, etc. The locals see no real benefit except having to pay more for everything. While more taxes are collected, most of that goes to offsetting just some of the economic pain induced by the people living there.
and it is in fact zero sum. every spot filled in university or company is a spot not taken by a local, as its obvious by the numbers, more local people are not getting admitted into CS programs nor are they being hired. its 100% zero sum when we are looking at these numbers and %s.