Before I get an electric motor bike, I will join a rowing club. No problem keeping up with others because we are all in the same boat.
For now, there are plenty of people to ride with if I want to test myself. And if I want to go at my solo pace, that is what I do. As I get slower, I can join slower groups. There are beginner groups where I can share what I have learned about riding my bike the old fashioned way. I cannot imagine finishing an electric motor bike ride and feeling the same sense of accomplishment as I do after riding one of my bikes.
I suppose it is just a different sport than cycling. Or a different cycling category. Like downhill MTB where folks get a lift to the top and ride gravity-assisted downhill. I am sure they get plenty of exercise. But it is not Cycling.