Anyone care to actually tackle why this is such a bad idea?
California is a big state, but in general, the climate doesn't require the heating needs of a gas-fueled furnace. That's hard for a midwestener or northeastener to understand, but population centers don't see -20F every winter. A heat pump is probably ideal and I'd be willing to bet most new homes have already gone that route.
Most major municipalities in California have already banned natural gas-fired appliances. A good portion of this already doesn't affect 80% of the population.
For a personal perspective, homes without a gas-fired furnace and appliances have much better indoor air quality. If I lived in a climate that supported it, I'd have gotten rid of my gas furnace long ago.
What about power outages? You use you furnace at completely different times and in a completely different manner than the *other* electricity hog: Air conditioning. A switch to electric heat (again, in the form of efficient heat pumps) will not have nearly the same electricity-usage impact as the already-existing maximum demand.
On the topic of power outages, it's not like they're exclusive to California. Ask Texas about how well their gas-fired state does in extreme weather. They seem to have trouble keeping the lights on and homes at a comfortable temperature with gas.