You speak of an already dense place laid out like New York City, or maybe Japan. Where there are regions that HAVE density and typically a matched civic infrastructure.

I am speaking of most of America, where that is NOT happening because densification of areas is blocked by those already nearby who like the way suburbs near jobs are. (I don't blame them, apartments and probably condos SUCK, the building codes don't protect me from the choices of those nearby so everyone suffers the most annoyance.)

In effect, I am encouraging at least some of those nearby areas to experience zoning upgrades. Like in a city simulator when low density residential gets replaced with high, and mid and high rises replace older single family homes and suburbs.