Adding to this, we've also abandoned the idea of building out in the middle of nowhere and linking it to a city center with a rail line. I'd gladly buy a cheap home in the boonies if I could take a train into work instead of driving.
What we've built instead for more than half a century is continuous radiating sprawl.
Even suburbs cannot afford all of their ongoing infrastructure obligations, and why you see many dilapidated areas.
This is all becoming apparent now because birthrates have plummeted hence what used to be masked by economic growth due to sheer population growth no longer has the ability to be papered over with increased tax collections due to increased population.
Then we can run autonomous vehicles (private and corporate) over the same infrastructure.
Unfortunately, there's talk of shutting it down[2] due to low ridership stemming from the pandemic.
[1] https://www.metrotransit.org/northstar
[2] https://outline.com/smYCML (startribune.com paywall)