After watching the political quagmire of the housing crisis in California, this gives me some hope that The Big One might create a situation where it would be possible to reboot the architecture of major cities to prioritize humans over cars without significant loss of life.

And yeah, it would really suck in the very short term. In the years following the quake, there would be a boom of work opportunities. Contrast to a situation where the buildings are spared at the cost of human life, you'd have ghost towns that would rapidly deteriorate to the point that the buildings would also fall to ruin