Of course, crime, housing costs and traffic (caused in large part by bad urban design) are real issues in American cities to varying degrees. But it's not as if all cities are lawless slums without any way to move about.
I shouldn't exert myself pointing out that the average cost of a vehicle is about $5000 per year [3], which costs a lot more than the unlimited miles you can travel with a $75/month bus/train pass in Chicago. [4]
It would probably blow the minds of car-dwellers to find out that it only takes 20 minutes to walk a mile. [5]
[1] https://realestate.usnews.com/places/new-york/new-york-city/...
[2] https://www.nyc.gov/site/doh/health/health-topics/obesity.pa...
[3] https://www.move.org/average-cost-owning-a-car/
[4] https://www.transitchicago.com/fares/
[5] https://www.nike.com/a/how-long-does-it-take-to-walk-a-mile
Which means you have massive delays between stops, and can’t do much if you don’t have hours available.
Especially in a city like NYC, essentially everything you need is within a mile. I live in Tokyo right now, and everything I need for daily life is within a quarter of a mile. I can get basically anywhere in the city in 30 minutes.
You know cities aren’t all like that?
I lived without a car in SF for 10 years and I think it covers that city as well. A lot of international cities work the same way.