1. NYC wealth dwarfs the rest of the US. You're right in that it's a good pool, but there isn't the aggressive experimentation in tech that SF has. I attribute that to culture, bringing me to point #2.

2. The Puget Sound region is 2 million, roughly. Seattle is 650K, roughly. These are not huge by any global scale, even in the American scale. As I am reminded by the Seattle Times, the PI, and the Stranger (particularly), techies are not really welcome by the True Seattlite, and we aren't Welcome - (this is even true on reddit r/Seattle, which is the techiest of the techy). The grandiosity and merchantilism that characterizes NYC and SF isn't here. It's more about getting up at 6, working out, working hard 8-5, then going home or the bar, turning in at 11. Not doing whack experiments in a coffeeshop all night long to turn into a company. Generalizations, I know, but it's a constant drumbeat; it's the way the city is.