I'm an aging millennial, but on a purely personal level, when I lived in a city with good public transit, I was a lot happier, most of the time. I really like stepping off the train and the bus and being on my own two feet, the walking exercise, not being chained to this thing I have to worry about. I hate driving, I hate parking, I hate owning a car--the maintenance, the ongoing cost of fuel and insurance, all of it…
To me cars, equal freedom. I grew up in a small neighborhood, I rode bikes to my friends houses there but my neighborhood was so far removed from other places and stores that there was no other place to go. Getting my license at 16 opened so many doors for me. Now I could go hang out at my other friends houses that lived 10-15 miles away from me. I could get a job, go to the store and movies, and just cruse around without having my parents question me. I didn't have a cell phone back then, so being able to leave and not be contacted was glorious.
For college I moved out to the Texas Panhandle. When gas was cheap I'd often go out for long drives into the country with friends, to talk, so explore and see what was out there, to visit family, and to make beer runs because our city was dry meaning you had to go out of town to buy a six pack.
When I have had extended periods of not having a vehicle I have get a visceral sense of foreboding and dread. I feel like a caged animal, unable to leave any situation, escape in case of danger. These feelings mildly lessen if public transit is available, but they are still there. Having any kind of vehicle feels like safety as I know I can flee if I need to, even if I don't.