I also grew up and was educated in Silicon Valley and have lived and worked my whole professional life there.
It started with Stanford University (and Santa Clara U), Prof. Fred Terman, Bill Hewlett and Dave Packard, Bill Shockley, Gordon Moore, Bob Noyce, Jobs and Wosniak, Bill Perry, various defense aerospace companies, and *many others* cultivating Silicon Valley way before the 1990s, going back to the 1950s-1960s. It has always been a desirable place to live (excellent weather, easy access to the ocean/mountains/recreation, etc), and of course, work.
Seems this needs to be rehashed every decade. Life goes on, Apple will continue to do great. I would not want to live in any other area.