Those are all "e-motor" bikes. The only distinction that really matters is motor/ no motor. The others are artificial, created by the current regulations. Certainly there are cyclists who age out or otherwise become unable to ride w/o a motor but I think that will be a small segment of ebike users in the future. The attractions are obvious and as prices come down I think most users will come from outside the cycling world. They aren't going to care about classes. The "it's riding a bike, the motor is no different from another gear" prattle we see here will just seem silly to them. I agree, terminology is vague, hope this clarifies what I meant.