Yes and no, people get stuck in economic traps of paying for things they didn't really need, and those can eliminate all free time. Also, there really is a large group of americans that still work multiple jobs and can't afford healthcare, thats a thing. Some of those are physical jobs, but many are not.

Maybe, but many people in the world are able to stay healthy without having to make the time commitment or discipline of regular explicit exercise. It just falls out of living their regular lifestyles.

if you have money, it's a lame excuse.

food deserts are real.

not having enough free time to exercise is real.

If one has the time to spend on HN, they could spend it exercising. They won't, but they could.