Be concerned. Have a plan.
Consider attacking your living expenses. Request a rent reduction from your landlord -- you're a known entity, and they're more likely to offer this if you ask than if you don't, and them more they've heard that request. Look at roommate situations. Don't make any big purchases. Do put away an emergency stash.
One of the big problems the Bay Area faces right now is one that attacks its ongoing attractiveness as a tech hub: technical labour is losing its flexibility. Employment is contracting, slightly, but housing is so expensive that virtually nobody has any personal runtime if the paychecks stop. A considerable exodus from the area may make it less attractive in future. It's one thing to take a new job down the street, or even switch between San Jose and SF or SF and Oakland. It's another to shuttle back and forth, with household wares, from Cleveland to Palo Alto, every 6-18 months.
It's also an opportunity for a new low-cost hub to establish itself. One with what makes SV tick, but doesn't have its problems.
Unfortunately, most of the candidate destinations lack the legal environment, particularly labour law, which made SV so attractive. It's possible locations outside the US might emerge, though I'm not sure where that might be either.
I'm not calling the end of SV, that would be idiotic (until its not, at which point it will be inspired). But the hub is entering a period of distinct vulnerability.