” A powered bike provides the exercise of a couch.”
You have no idea what you are talking about.
But don’t worry, going on about things which one knows nothing about is becoming quite the tradition here on FR, so you aren’t alone.
I admit that I overstated. It depends how they are used. I have seen young people zipping along a level trail with no exertion. They are missing out IMO. And then there are bicyclists who ride as though they intend to compete in the Tour de France.