I would argue the core issue is actually overpopulation (or in the case of California too many people wanting to live there but also trying to balance preservation of Nature). And it's certainly much more acute in California. Tokyo is not a desirable way to live, but neither are the suburbs. Too many people means the density gets too high, and poor zoning regulation and poor building incentives get us mcmansions. Every little European city that you've ever been to that was lovely, walkable, and sensible, is the objectively best way for humans to live. You know it and I know it. Loosening building restrictions won't really work if you think that you're going to build single-family homes. It would be a disaster. You have to build entirely new neighborhoods where people can't use cars at all, but I've never seen any level of government in the US allow that. Otherwise you will just end up building suburbs and then the state will build 15 lane highways ad nauseam. Traffic will continue to get worse, it'll be a dystopia.
And you build more and more housing, you'll wind up with 4-lane highways to and through Yosemite or something - that's not at all desirable is it? How would you handle the traffic and flow of people? Giant hotels, McDonalds, and huge traffic stops? It's just not sustainable.
California's problem is that it's not sustainable for the amount of people that want to live there. I think it's a global problem in general too. Less people, and no cars would be most desirable to me.
Sorry for a bit of a discoherent rant.