If all the value is how much land you have, like the author claims, then people would just build a mansion in South Dakota.
It's not just LA, NYC, and San Francisco anymore. Home values are rapidly increasing in places with declining population (Pittsburgh metro, e.g.)
Like where my parents live. There are several people they know that are selling there just because their homes have shot up so much the past year and are renting until the market cools down.
Our house isn't on the market, but the Zillow estimate has gone up 26% in the three years since we bought it, most of that in the past year, and we're not in a major city (far suburbs of one, though).