One of the many dysfunctions in transportation and land use planning is our collective inability to recognize the difference between city and country.
It’s really not that hard. In the country distances between buildings are large, while in the city they are short. In land use jargon, densities are lower in the country than the city.
The most useful form of transportation varies between city and country.
In the country, individual, point-to-point, on-demand service (foot, horse, bike, car) saves a great deal of time over feasible shared, scheduled, fixed-route services (transit). That time savings offsets the individual cost savings from sharing a vehicle with other passengers.
In the city, shared transit services are on the whole less expensive to the user and society than individual services. The small increase in time is offset by cost savings from sharing. The greater density allows more frequent service and more direct service nearer the traveler’s trip end points.
In idealized low-density places like Wright’s Broadacre “City”, local transportation was clearly individuated, to the point it appears everyone has a private gyrocopter.
In Howard’s Garden “City”, individual transportation was used to get around town, and to the inter-municipal railway.
In Jacobs’s New York City and Toronto, walking was used to access transit for longer distance urban and inter-urban travel, while the car was not especially welcome.
From both a transportation and land use perspective, each of these works on its own terms (assuming gyrocopters actually work).
In short, in the current technological environment, there are two stable points: one where a sufficient number of people have abandoned their personal cars and use transit daily that transit is sustainable with high frequency and ubiquity; and one where people keep their cars and use transit on special occasions (to go downtown or the State Fair for entertainment, e.g.).
Once the car is owned, the marginal cost of the additional trip to most destinations (since free parking is found for something like 99% of all destinations in the US, gas prices and taxes are low, and we don’t have road pricing) is sufficiently low it outweighs the combination of low costs of shared transit vehicles with higher travel times.
A metropolitan area is large enough to contain multitudes. There can be a center where people can live car-less because the transit (or walking or biking) is good enough for daily city-based work and non-work trips, and a countrified-edge where people can live transit-less, since living and working in the suburbs is seldom a market transit can well serve (except as an accidental spillover where people are lucky or skilled enough to have home and work aligned on the same radial transit line).