But there are at least three additional factors that make suburbs even worse.
First, almost all new suburbs in the US after WWII were built with racial covenants. New school districts followed community boundaries, essentially making suburban school districts into the new Jim Crow. The US Supreme Court ruled in 1974 in Milliken v. Bradley that states had no obligation to remedy this discrimination. In this way, suburbs and their corresponding school districts were the engines of apartheid in the US during the second half of the 20th Century.
Second, to maintain the charade, it has become a time-honored tradition in the US to use the FHMA and the Fed to artificially manipulate housing prices, keeping them artificially higher than they organically would be if the true cost of sustaining suburban infrastructure were honestly apportioned. This is done to prop up the “on paper” national net worth. It’s the economic equivalent of a Potemkin Village. It has prolonged the reversal of this style of development, allowing it to grow larger.
Finally, there is the impact on families, especially extended families with older family members. Access to homes is almost solely via driving. In many suburbs, walking is affirmatively dangerous due to curvy roads, dense foliage, and lack of sidewalks. Further, there is nowhere nearby to walk to. People enter their homes via the garage, close their doors, and stay inside. Community breaks down. Older people are virtual prisoners in their homes. It is anathema to humans as social animals.
Well, when suburban sprawl started we were much more of a manufacturing country with factories all over supporting these communities. A tremendous amount of that is gone. Of course after WW2 we and Canada were really the only countries capable of rebuilding Europe and Japan which really fueled our economy. You fail to mention the utter destruction and crime that took place in our cities during the 60s and 70s which drove the middle class from the cities. We are starting to see that again just as the American cities have been coming back.