We aren't going to rebuild our cities around bikes, and even if we did, a large number of people could not use them. On the other hand, we already built our cit

We aren't going to rebuild our cities around bikes, and even if we did, a large number of people could not use them. On the other hand, we already built our cities around cars, and self-driving cars would fit right in (if they actually worked). Car makes us less us sedentary and less able to walk. Bikes work the opposite way, and encourage us to be more active and more able to walk. The elder can't walk due in part because they didn't engage in enough physical activity, which in turn reduce their activity level. Beside, we won't be able to redesign our urban architecture overnight, but with progress comes dividend that will make further progress much easier. There will always be edge cases for people who are disabled and who are too obese, but I am confident we can find mobility options for them. A healthier society will have more money to support the hopefully dwindling reminders who can't use bikes.