It's not really true. Almost every neighborhood in Atlanta has a cluster of shops or food hall kind of thing to walk to.
It's true that it's a massive lifestyle leap to go to no car. But walk to the park. Walk to get ice cream. Ride bike to school are all easily doable in atlanta.
It's certainly true in Atlanta. That "cluster of shops" can be a long way walking (10-15 minutes) from where one resides. It's small, incomplete, inadequate, etc.
I grew up in Atlanta proper, so know the city well, and later, by choice, lived there for a few years as an adult without a car and it was genuinely complicated. I chose a place to live near my place of work (near = it was 30 minutes solid walking). I had access to a supermarket (15 minutes walking), two (!) transit (MARTA) stations each at 15-20 minutes walking, and several bus lines (none with frequency greater than 30 minutes nor standard deviation less than 20), as well as the "cluster of shops" to which you refer. It had a bar, a few restaurants, a laundromat, and a drugstore. For real shopping other than food I took MARTA to a mall. My morning walk to work around 6 o 7 am required crossing a street used by prostitutes and drug dealers. They didn't bother me but the cops were suspicious of me for being there on foot and more than oncee I had to avoid cops with guns out chasing someone down.
People there generally considered me nuts for choosing to live this way.
I remember fondly that on my way to work there was a street full of pecan trees and at the right time of year I could get a handful from the sidewalk (there were sidewalks!).
When I was growing up (true, this was a while ago), again in the city proper, the nearest park was 3-4 km away. I went there by bike and played pickup basketball or went to the public pool, but it wasn't exactly nearby, and it wasn't walkable. Ice cream bars could be bought at a convenience store several km in a different direction. The bus stop was near the park and the bus came every 50 minutes, with considerable variance. On it it took something like 40 minutes to get to a MARTA station. A single to and back trip on public transport could easily take 3-4 hours in total so I didn't do this often. My school was around 12 hilly kilometeres away, a bit longer if one avoided the interstate. Biking there required riding on heavily congested roads with no shoulder and dealing with drivers completely incomprehending of cyclists and later crossing 8 lane roads and facing considerable danger the whole way. It could be done and I did it, but it was not particularly safe as there was no way to get there without dealing with rush hour traffic accessing the interstate.
I vaguely remember that there was a store within walking distance that sold automobile tires ...
There are some places in the US--probably Manhattan most obviously--where there's a culture that doesn't have the expectation that you have a car. But, while people living in most other cities can basically do a post-university lifestyle without one even in cities with relatively good public transit, a lot of their friends probably live outside the city, a lot of activities depend on cars, etc.
I do know an adult couple in SF who gave up their cars but I'd observe that they rely on Ubers and various rentals a lot. I don't think I know anyone in the Boston/Cambridge area who doesn't have a car. Of course, they exist but I don't know one.