Also, no, California really isn't that crowded. Italy has something like 30% more people on less land, and still manages to be a massive tourist destination because it is amazingly wonderful and beautiful, from the mountains to the cities to the seashores.
I say this as someone who lives in the one of the states that West Coast politicians want to steal the water from. Instead of shipping our water across the country to feed the desert, you can... you know... just move here. So the water is fed back where it came from.
Sure, some jobs will go elsewhere, but there are big returns to being where everyone else is. This book does a good job explaining why:
SF residents use 50 gallons/day of water. Compared to 85 gal/day average across the state.
Feel free to take long showers, and water your lawn. It is a literal "drop in the bucket" when compared to the actual large industrial water users.
Tokyo is not a counterargument to the parent’s point that geographical constraints dominate housing costs in the bay area.
San Francisco's never going to have 10 million people, but the Bay Area could sure add a lot more. Look at, say, Palo Alto with all its single family housing.
Obviously, the vast majority of those California permits are going into the major cities, which are the places that have the geographic constraints.
If you want to make the comparison, do it on a properly normalized basis.
You know nothing about Tokyo, especially its housing.