The value of some places is the very fact that they're low density.
Exactly. Just look at a satellite image of Atherton, CA or Lexington MA; they're low-density residential places with plenty of greenery where each lot is sizable and crucially, near major economic centers with plenty of high-paying jobs. They're desirable precisely because they allow you more breathing room while being geographically close to the hustle and bustle of a big city.