I mean, things aren't really that different from when the Loma Prieta hit. Most of the people who died in that earthquake were on the bridge when it happened. It caused a lot of property damage and injuries but not many fatalities.
> If the entire zone gives way at once, an event that seismologists call a full-margin rupture, the magnitude will be somewhere between 8.7 and 9.2. That’s the very big one.
I'm not well-versed in earthquakes, but from what I know the Richter magnitude is logarithmic in scale, I can't really even imagine in my head what a 9.0 quake is like.
I'm glad OP / someone is asking these questions, I often wonder about this myself, being a tech worker in San Francisco.