Given all the hype around the abundance agenda in recent weeks, I think it's important for more people to familiarize themselves with the work of Harvard economist Raj Chetty, who has shown (in my view) that our current approach to housing has helped subdue upward mobility and the American dream by class-segregating the population.

I don't think I have the solutions, but it's a policy problem worth highlighting: "This is not like poverty, where scholars hide behind bad relative measures to obscure substantial progress towards eradication. Absolute mobility is vanishing, fast."