You said "there are homeless people everywhere", which is technically true but omits quantity, and especially quantity compared to wealth.
I'm not as positive as you are about what makes California (and Seattle) create/attract so many, but it's definitely an outlier compared to "everywhere".
Yes, if you didn't understand my point: there are homeless people in every society, but most do not have as many as silicon valley because they pressure them into accepting the help necessary to restore their ability to make rational decisions. Rational people do not choose to live outside on the sidewalk like rats, people who are drug addicted and who have untreated mental illness do.
I'm not as positive as you are about what makes California (and Seattle) create/attract
The weather is pretty nice, much more stable than in the east coast.