Outside the US, there are many examples (Japan and China both do this).
In the US, I don't know specific examples, but you can definitely use a combination of policies (building public transit, zoning laws to encourage high density, making parts of the city more pedestrian-friendly - and generally less car-friendly) to encourage high density.
There’s photos of subway stops in random fields in china that sometimes get laughs but in actuality china is just smart enough to build the subway and THEN the buildings.
Meanwhile Japanese rail companies own land where they build rail and can make more money on the land than on the trains
Doing it after the fact is much, much harder.