1) How expensive and disruptive to build would "good transit" actually be?
2) How much do people appreciate more direct point-to-point transportation?
This incident occured in a town of 51,000 people with a density of 1,700/sq mile, that looks like a suburb of Salt Lake City which itself has 200,000 people with a density of 1,800/sq mile.
What's the cost and timetable for turning that into a transit-friendly city even if everyone wanted to have smaller homes in a presumably-more-dense footprint?
On the other hand, self-driving cars would sit on top of existing infrastructure to enable even more personal privacy and land use. So even if people were 50/50 which way to go, the latter would likely be far cheaper.
If you go back 100 years and prevent cars from ever be mass-produced, yeah, American cities would've grown and suburbanized in a more British, rail-oriented way. But reversing that would be far, far harder.