This varies considerably. There are many places in the US that are entirely car dependent (nothing within walking distance, and little to no public transportation).
Or you can walk 5 miles each way. Maybe it's good for your health (though the winters might be brutal where you live, and your route might not have sidewalks, and walking into work covered in sweat in the summer might not be allowed where you work), but that's pushing 2 hours each way as well. Getting a bicycle would reduce the time requirement, but most streets in the US are pretty bike-hostile, and you still have the weather issues to contend with.
Sure, technically a car is not "required" in that scenario, but people who are poor essentially have their time as one of their few precious assets. Saving 3-4 hours a day on a commute could mean picking up another job[0] that helps reduce financial insecurity just a little bit, or allowing a parent to spend a little more time with their kids.
I think people just really don't understand what it means to be poor. I have (fortunately) never experienced it, but have heard enough first-hand accounts to get the gist of it. Everything is harder when you don't have money. Everything.
[0] And that's a whole other issue, that so many jobs don't pay a living wage, requiring someone to hold down more than one just to make ends meet.
But in general... walking 5 miles each way doesn't sound impossible? Back before the pandemic, I walked 6km each way to a social gathering every week. I often walk errands up to ~8km each way.
Cycling... I used to cycle to work 12km each way year round, in temperatures as low as -10°C. Challenging? Yes (I didn't have especially fancy clothes and my hands were freezing). Impossible? No.
Public transport is nonexistent in several places here in Texas for example - you have to have a car (or know someone who does) to get to your job in the first place. But commuting puts wear and tear on the car, especially if you can't find work particularly close to where you live.
Yes, there are some places where public transportation both exists, doesn't take most of your day, and is cheaper than cars. Those places must be great, but as a 3rd worlder I barely know them (it's not a huge problem for me, personally, it's just enraging).