Ignoring that every implication of this post is super racist, mostly I'm confused by the idea that the SCARY HORDE OF INFINITE BROWNS that fills the fever dream imagination of opponents of open borders would not be heavily focused on moving to areas like Silicon Valley for precisely the reasons you state. Wealthy area, dynamic land of a growth industry, full of chances for smart young go-getters of precisely the sort most likely to up roots and relocate. The place is a globally iconic byword for opportunity and dream chasing. When ole mate says he has "skin in the game" surely that includes being in a place heaps of people want to move to who currently can't. I mean, this putative human tsunami of dastardly foreigners is hardly going to concentrate on slathering itself all over Arkansas or wherever now, is it?