> There are a lot of very fat people, old people, disabled people, and so forth who could not ride a bike half a mile. Maybe many of them wouldn't be in that s

> There are a lot of very fat people, old people, disabled people, and so forth who could not ride a bike half a mile. Maybe many of them wouldn't be in that state if their normal day to day activities involved cardio? Sure, some people health conditions have nothing to do with their exercise level. But having a lot of people who couldn't ride a bike half a mile is not the expectation. People can ride bikes until pretty advanced ages. We can reserve cars and other transportation for people who actually can't use anything else.