@shadyspotlight @jcalais @qag Rochester NY had an extensive streetcar/trolley/lightrail system and a subway line in the 1950s. When the streetcar system aged enough to need a refurbishment project, auto industry lobbyists bribed the city council to scrap it and replace it with busses (so that cars wouldn't have to wait behind streetcars - ignoring that busses of the time were loud, smelly and a less comfortable ride). The same thing happened in lots of other small cities at around the same time.
I live in a town of 8,000 people that's very walking accessible because it's so dang old, cars weren't invented yet when the overall layout was established. They've made it work as a destination for people who arrived from the surrounding rural areas by car, by making a few large parking lots around the edges of the town core.
I agree with underground roads not being the most practical option.