Becuse you NEED a car in the US.
There is no way around it most places in the US.
We have an incredibly high car ownership rate. and you really cannot function without one. Most cities are built around car ownership, If you don't have a car what you can do and where you can go is very limited.
Public transit is limited has short hours, is dirty, unreliable and dangerous, and generally things are wildly spread out. And the better and often more fun things often have no access at all if you don't drive there.
The only things in my city I can think of well served by public transit is the Casino, and the Mall of America. And its not as much transit as trucks to bring the sheep in for easy shearing.
All forcing this wound do is keep poor poor off the road. They can keep the automatic car. I'll keep driving my 74 Beetle.