SFBA is not a good place to hire engineers, unless you're heavily funded AND a clear winner and need to hire a bunch of diverse types. For anything else, I could find other places which are far superior.
It's a great place to hire professional services to support startups, and the best place in the world, hands down, to raise money. YC being here makes it great early on, too. I think investors become less location-sensitive as you get to later stages, if you're winning.
The biggest problem is if you're selling b2b to tech companies at all, you can literally bump into your customers here.
With my next startup, I plan to do Seattle (probably) or Austin for a US office, with a small SFBA presence, and then Berlin, and run EU and US companies as separate entities with separate officers, so people can choose if they want to be customers of a US or EU company. Maybe add other location in the future.
(I'd obviously be doing something in the infosec space, which is becoming increasingly jurisdiction sensitive.)
I absolutely encourage people to work in SFBA for a while to build a network, but after that, GTFO unless you really want to be here.