Pretty confident if there were a 1989-level earthquake, most startups and tech companies would just decamp to somewhere else for the recovery period. The easiest is when you already have an office somewhere else (we have London and soon Asia, although SF is still far larger); I'd probably pick Hawaii or Seattle personally.
It's easy enough to find an off-season vacation destination and move everyone there; essentially anywhere is cheaper than SF, so that's easy. Not every company has to move to the same place.
It'd suck to be a service-industry worker in SFBA after an earthquake, but tech employers can just move, and hire service-industry people to fix up their offices for a few months before returning (or not).
(this might not be necessary after a 7, but after something insane like a 9, would definitely happen)
It's easy enough to find an off-season vacation destination and move everyone there; essentially anywhere is cheaper than SF, so that's easy. Not every company has to move to the same place.
It'd suck to be a service-industry worker in SFBA after an earthquake, but tech employers can just move, and hire service-industry people to fix up their offices for a few months before returning (or not).
(this might not be necessary after a 7, but after something insane like a 9, would definitely happen)