There’s plenty of large houses in SoCal. My realtor friends sell them for cash these days to a largely Chinese clientele.
Last time out it was the Japanese buying up commercial property like crazy. Didn’t work out too well for them.
The problem with affordability comes from zoning restrictions that require large lot sizes and discourage multi-family dwellings. Chinese plutocrats can certainly afford mansions in Palo Alto. Domestic working class stiffs can't even buy a micro home, because they're probably prohibited there and most of the areas that are close to work (i.e. near major CA cities like SF, SJ, LA and SD).