Great points, guys.
In addition to what Bobby5280 said, I think mass transit for those in non-urban areas is very time-consuming and complicated, especially in comparison to owning a car. I don't doubt that using mass transit really works in dense urban areas, but the truth is that outside of New York, San Francisco, and some other bigger cities, America is really spread out. Using mass transit in a normal American city would look something like this:
1. Get to mass transit station, either by driving, walking, or biking
2. Wait for mass transit to arrive (probably a while)
3. Ride mass transit
4. Get off mass transit
5. Walk to destination or transfer to other mass transit option, repeat steps 2-4
Meanwhile, using a car or ride-hailing service looks like this:
1. Get in car from starting point
2. Drive to destination
3. Park car and get out to destination
Driving a car, in most scenarios, would probably take a lot less time than the mass transit alternative. For mass transit to work in America, it would need to be extremely comprehensive, which given today's costs for building such mass transit infrastructure, would probably cost at least tens of billions of dollars for a city the size of Peoria, IL. And there is no such thing as a free lunch.
Not to mention that if you don't have a car, the easiest way to run errands is to stack them all one after another on one day so you don't have to repeat that 1-5 process multiple times a week. Plus having a car (or even a ride-hailing service) means having freedom. You can pick up your kids from school, you can react to emergencies quickly, and you can take your guitar to your friend's house across town for a fun Saturday afternoon jam session. Can you do any of that without a car? Maybe, but it would certainly be annoying.
Plus, (pardon my kernals12-esque ideas here) I believe that very soon the advent of autonomous cars, electric cars, and ride-hailing will allow for cheaper maintenance, less fuel costs, and more free time while driving, which I think are some of the big problems people have with owning cars right now.