One of the reasons why ebikes could become a popular transportation solution is because they can supplement a car without having additional license and registration costs. That is very very important because if they don't save someone money overall people will just continue to get in their 6000lb SUVs. I can honestly state that the auto industry is pushing the 3 class system to eventually push for registration and insurance requirements on Class 3 just as they did in Europe but everyone calls me a conspiracy theorist on that claim. They ignore that the largest auto parts company provided $3 million to People for Bikes to lobby the 3-class system state by state (I believe they even drafted the legislation for People for Bikes). I have tried to get everyone to support the federal definition in HR727 which was fine for over 12 years in all 50 states but many people then get into the states rights claims. In my opinion the feds define the "what" and the states control the "use" - the where, how, who, etc.I’m not wise enough to know exactly where to draw the line, but I think it’s reasonable to require licensure and insurance at some speed. It’s also probably reasonable that at some speed a two-wheel vehicle should be built to heavier and more durable standards than a Wal-Mart bicycle.
I suspect that anything that can roll with the flow of traffic on city streets should probably be licensed and insured. There are plenty of YouTube videos that illustrate the point pretty well.