Whenever I run into an argument for something society-wide like this I do a little though experiment: Imagine the world as the argument suggests - in this case that public transportation is the norm. Now imagine I came to you and said, hey, what would you say to a personal conveyance device? Small and cheap enough to park at your residence, can carry you and all your friends/family/churchmembers/whatever as well as their cargo, and there's an existing, nationwide system (highways) they can use to literally get anywhere in the entire continental US, door-to-door, with the only requirement that you pay a little more.

Virtually everyone would dash off their shitty trains and busses in a moment and hop into cars. Even if you told them it would lead to mass congestion they'd point to people whose job it is to stuff people onto trains when they get too full. If you told them it would lead to pollution they might be swayed, but then if you told them electric cars were basically right on the horizon that would seem like an acceptable trade off.

You are arguing for a world that for most of the US would be considered objectively, demonstrably worse than the status quo. Just because you and your personal social circle lives in urban areas and doesn't need or want cars is virtually irrelevant to the national conversation because you are a tiny fraction of a minority that is not going to get any traction as self-driving and electric vehicles become the norm.

Public transportation in the US has already hit its apogee. Nobody wants it outside of dense urban cores, and the nation is largely not urban cores, nor will it be just because you wish it was.