I think a big part of this is that suburbanization created a tremendous amount of (government subsidized via infrastructure) value that in many metro regions has all been scooped up now. There’s not much left to build outward, no arbitrage, and not enough political will to fix it (or: too many people benefitting from capturing the value).

And in combination globalization/corporatization has put a lot of high paying jobs in a small number of areas.

In my opinion it’s basically generational warfare or at least a hidden retirement tax paid for by professionals in booming cities for old people who happened to own property in those cities. Even if you don’t subscribe to that hot take, it should be uncontroversial that property values massively outstripping wages in some areas reduces quality of life and contributes to inequality.