This general topic seems to come back into focus on a regular basis on HN (last time, 1 week ago). People have been leaving SV in numbers for the 30 years I've been here, always citing traffic & cost of housing as the primary reasons. Though this time, you could add decriminalization of petty crime. Nonetheless, the population growth remains net positive. The fundamental design of the Internet was to be robust agains…
Smart, ambitious people tend to congregate, and capital follows. If during past exoduses, people moved to random places, I can see why SV remained the primary magnet. But, this time everyone seems to be moving to Seattle and Austin (based on my anecdotal experience of ~20 SV startups that have moved to Austin in the past 6 months).
Other things that make this time different: remote work being generally acceptable & higher state income tax
Of course, "every time is different", but eventually SV will fall. The question is just when and what the right conditions are.