As a Californian living in the central valley, where we never get snow, I had never heard of snow tires until I lived in Germany, where seemingly everyone had them in winter. Nobody around here has them or even sells them.

When we go up into the mountains in winter, either the roads are cleared and we can drive on them with normal tires, or it's snowing heavily and we put snow chains on the tires and drive slowly. I've only had to use snow chains a couple times in my life because I generally only go into the mountains when it's not currently snowing, which is most of the time.

Climate change has made the climate drier here, the mountains get a lot less snow than they used to. It also helps that real winter with snow storms only lasts about 3 months.

I'd imagine most Californians are using chains or other traction devices rather than snow tires. Snow tires would be awful in the Bay Area or pretty much any of the state's main cities.