I agree that based on average income to SFH price, their is no correlation. Most people that I know that got into house in an expensive neighborhood are people where family helped out or parents died or grandparents died or something.
San Diego now, not before the 80s, is a victim of outside money raising housing costs. Uber rich guy from China or New York overpays for a house in RSF or La Jolla, Doctor gets priced our and moves Encinitas, Engineer gets priced out and moves to Rancho Bernardo or Carlsbad, which prices out Policeman or Fire Fight which moves to Temecula.
Temecula has single handedly saved San Diego from a major labor shortage. I really wished the government would keep statistics on foreign purchases of real estate and mortgage vs non mortgage properties, so you can really see the true picture of housing.
Because if you 10,000 houses that are 2,000,000 each but don’t have a mortgage you can’t say we have a housing affordability issue.