[ghaff]

One thing that probably distinguishes Silicon Valley from other high-cost areas is that it's almost uniquely difficult to get out of the high cost zone while maintaining anything like a reasonable commute.

Metro Boston/Cambridge is pretty expensive these days as are some especially tony suburbs but you can get out toward reasonable property/rents relatively quickly. And, with the exception of newer outposts of companies from SV and elsewhere, a lot of existing tech is outside the city anyway.