I'm not really saying it can't be done. I'm just saying that, comparatively, this puts the US at a huge disadvantage. It requires a larger investment per rider, and when you're done, you still have a metro area that was specifically designed to be convenient for drivers that your transport system must compete with.
I worked a job for several years where I could have taken either bus or light rail to work. I still chose to drive because I already had a car, my car had more privacy, I didn’t have to go outside in the weather, and I had more autonomy.
For public transit to compete, it has to be someone’s best option. Being usable is not good enough to cause people to switch.
Yes, you could build it all anyway, and that’s probably the only long-term solution. But it’s not politically popular. If not for budgetary reasons, then because people don’t want construction interfering with their drive.
In the end, I feel like we’re better off just concentrating on public transit in the neighborhoods that want to use it.