Occasionally, advocates will express the sort of extreme end of urbanism: all buildings in growing cities should be high-rises. It’s not always clear whether this position is made tongue-in-cheek or seriously, but we’ll go ahead and treat it as a serious proposal here. After all, at least some people advocate it in seriousness and it’s an easy position to arrive at: if denser building is better, than even denser building is betterer, right?
Even a casual read of the construction types page or Affordaville should show the issues this presents: high-rise construction is very expensive. Limiting all new construction to high-rise excludes the possibility of housing people affordably in places where land values aren’t high enough to justify. Even in the Bay Area, while there’s surely enough demand for high-rise living to make high-rise economically feasible in some places, a broad upzone of all of San Francisco to mid-rise would instantly bring so much new housing that high-rise would no longer be profitable in many places it currently would be.
Essentially, this is a mirror of the issue with missing middle as a solution: it works in some places, but not all. Though in the case of missing-middle, the places it doesn’t work could probably do with denser construction and in the case of high-rise, less dense.