Your line of reasoning reeks of Europe worship with a token exception for obfuscation purposes. There are tons and tons of people who live in places like Boston and SF and Chicago without cars and do not feel any worse off for doing so. I used to be one of them. I would go so far as to say these people can enjoy all the opportunities of city life. Are they a majority? Probably not. But that's mostly a figment of how these cities absorbed their urbanized suburbs in the 20th century.
Even Europe isn't car-free; sure, if you're a tourist and you visit Rome you can go all vacation without a car or even setting foot in one, but the people who live and work there often have (or want) a car. And there are things you just can't do in Rome without a car or car-adjacent (Uber, taxi, etc) such as some activity in the suburbs in the morning, cross town in the afternoon, and central in the evening.
It's all about working with what you have available, not dreaming what could be available - would it be nice if there was a train stop half a block from my house that just happened to go exactly where I wanted? Sure! Is that going to happen? Unlikely, unless I change other things in my life to make it so.
