The question is why the decay in the center? And I think it is inextricably connected with why "growth", so-called.
It is easier, cheaper, and therefore more profitable for private developers to carve out single unit properties from virgin farmland, lay down utilities, and build, than in city centers. In places like Southern California, the land is perfect for this.
To redevelop city centers, is much more difficult, more expensive, and, of course, less profitable. Infill, a technique of building inbetween the spaces in the already built, is not convenient to typical developers.
The other problem, is utilities and services. Denser housing makes electricity lines, water and sewer mains, public transit system, schools, hospitals, etc, etc, more economic, and more convenient.
But it's obvious, utilities and services are mostly public sector, especially in Canada. The current political fashion is to starve the public sector of money, and pour it into the private sector.
This is the formula for the continuing doughnutization, of Los Angelesation of all cities.
"The unalterable course of events in most American cities."
"Sprawling cities have little need for public transportation."
I have to take issue with these statements. Is there some rule of god that declares some things "the unalterable course of events"? Excuse me, day and night--maybe--but all else is what some people make for the good of themselves.
As Bob Dylan once said "Money doesn't talk--it screams." We hear the protests of so many developers that the only way to grow a city is to grow out. Or as DMan says up. But cities can also grow in. But all of this is too hard, too expensive, not profitable enough for private developers. (Where is "rugged individualism" when we really need it?)
So they strand workers in out of the way 'islands' of housing for those who can afford it, but not, say cars. Maybe we should let these people walk? I'm one of those people. Why should there be so many cars? Is this another one of these rules of god?
Again, it is the nexus of companies that make vast profit from cars, ashphalt, building suburbs, and exurbs, that have pushed this agenda for 50 years. And dismantled functioning transit systems, both public and private, in most American cities.
Profit perverts.