Assuming that the rapid suburbanization is bad, planners usually propose a mix of land-use controls, housing subsidies, and public transit. Just let government control land use. The California experience shows that more and stricter land-use controls increase housing costs and that housing subsidies to promote affordable housing increase taxes. When taxes and housing costs escalate, people trade short commutes for decent housing and more income.
Employers eventually follow.
And when land-use controls also prevent redevelopment, one sees cases like San Francisco. The Bay Area suburbs exploded, leaving behind a tourist city preserved in bureaucratic amber, populated largely by government dependents. The direct costs of California's land use controls are staggering. More than the land was worth. No affordable housing will be built on these lots anytime soon.