I can't speak to the rest of it, but concentration of populations is often extremely good for certain types of endeavors. Cities often have the surplus value av

I can't speak to the rest of it, but concentration of populations is often extremely good for certain types of endeavors. Cities often have the surplus value available to support speculative and "non-productive" cultural output. The rapid mixing of ideas and cultures often helps a lot too. I'd argue that it's good for California to have all those people. It's pretty hard to argue that it isn't, based on the cultural, economic, and agricultural output of the state. Now whether or not it's good for the people in California is another matter altogether. And I say that as someone who recently left CA for another state.