If I don't fancy pedalling I've got my motorbikes, so ebikes don't meet any of my needs...at the moment, but when I'm older I may not want to be manhandling large capacity motorcycles, and my knees might benefit from a little assistance. But right now, nah.
For society in general, I'm with Milkfloat. Most car journeys are single digit miles with a sole occupant, so there should be less cars and more ebike on the road. The cavalier manner in which car drivers guzzle resources, create pollution and endanger those around them is criminal, and is making me angrier every day. Ebikes everywhere would calm me down.