Interesting take but while there is some argument to be made for being outside... Cycling outside is not always better for you. Many people live in urban areas where cycling outside is dangerous and objectively worse for you due to fumes from cars.

I've lived in rural areas where biking outside was great and in cities where biking was prioritized but I've also lived in many places where biking outside put myself at a much higher risk of being injured than biking inside. Especially at night after work which is when many exercise.