There's nothing wrong with focusing on the Bay Area, that's certainly a big enough problem to tackle. But the title, graphics and first few paragraphs should be changed to reflect that.
I would say the way we think about this is that there is both a cyclical and structural housing problem in American cities. The structural piece is that: 1. there is a limited supply of land in near proximity to economic opportunity -- most of this land is concentrated in cities. 2. cities need a wide variety of people to live in them to function properly. 3. even if we paid all of those people a median wage, the median person will struggle to accumulate significant wealth while paying rent. 4. the banking system cannot be expected to take low down payment risk without making the entire system vulnerable to another housing crash. 5. therefore if no 3rd party equity exists, then the only people that will be able to acquire any land holdings will be the sons/daughters of those with existing land holdings (intergenerational wealth transfers)
Hockey. Stick.