A city in Japan would build new dense neighborhoods and a new commuter rail line to serve them. A city in California would refuse to build new homes nearby, so people are forced to live in a far-away suburb and commute 2 hours by car. Then Californians complain about increasing traffic congestion.
https://www.reddit.com/r/ImTheMainCharacter/comments/11aqayg...
Japanese people are NOTHING like Americans. Stop saying CA should build like Japan unless you're willing to kick out the loud assholes.
Besides, even if we're generous and say that half of California is too mountainous to live in and another quarter is too desert-y to live in, leaving only a quarter of the state's area suitable for habitation, that leaves roughly 40 million people living in roughly 40,000 square miles, or about a thousand heads per square mile. That's comparable to Israel or Belgium in terms of population density, and certainly not as though people are packing into Kowloon.