A massive chunk (if not majority?) of those top 20 metro areas are largely car dependent for most of their populations. Large areas don't have any public transit at all, and the rest is often designed to be actively hostile to pedestrians.

Try living without a car in these places, all in the 4th largest MSA.

https://maps.app.goo.gl/mHmGidZRJaKptHeL8

https://maps.app.goo.gl/5P4mW5iM6b5ab9Ve7

https://maps.app.goo.gl/JCiBgESKs5ZWqGny8

https://maps.app.goo.gl/E1iVwLCB28ooGhQL9

These are all in "urban" areas and a part of DFW. But how about Houston, the 5th?

https://maps.app.goo.gl/7yEAimERmyE1EGde6

https://maps.app.goo.gl/UKSQjPqifWUSv82H7

I don't know how one would even get groceries without a car.

And even then, you're then talking about less than 1/3 of Americans living in that mostly car dependent space.