But much of the outflow is quite easily explained by the Covid shift to remote work allowing everyone in the Bay Area to take their high salary savings and buy houses wherever they fantasized about living.
You can’t really directly compare to previous migrations because those all involved making a career-impacting change. This one required merely overcoming the activation energy of a house move. So the signal about the “cost of staying put” is much weaker than in the past.
This is not to claim that Silicon Valley / SFBA doesn’t have problems, just that the analogy to Detroit probably doesn’t work without significant caveats.