You ignored the ebrake element of 3-class that I outlined. Brakes are a requirement. I have never said the CPSC has any interest in use regulations but they don't want states defining or redefining a product that is already safety regulated. Obviously anyone could frame compliance with laws as voluntary because we humans can choose not to comply with them, but there are potential consequences.Because the 3 class law has nothing to do with what is required for sale of any bike. It is voluntary. If you want to ride on public infrastructure, you need to ride an approved bike. Your choice... voluntary. You don't have to ride on public cycling infrastructure. You aren't required to. You have other choices of places to ride. Just like mopeds aren't allowed on certain roads. There are other roads. Trucks are limited on certain roads. There's always other roads. I could go on, but you get the point.
I have it on good authority that when the CPSC says an ebike, within their description, is a bike they are referring to their safety specifications of bicycles. They even link to the bicycle safety specifications for a bike. There is no reference to where the compliant bicycles can ride or limits to local governments on use restrictions. The CPSC has no opinion on use. An ebike is a bike means it has to have all the safety equipment of any bike for it to be sold. It really is as simple as the CPSC wants sellers to equip ebikes with all the safety equipment of any bike. They spec reflectors, pedal size and all the other tidbits on any bike. If you ask the right people an open ended question, meaning no agenda and no insinuations, you can get the answers.
Reading the CPSC mission statement it's very clear what they are and what they do. No rulings or opinions on use.
Here's a curious thing. None of their specifications are required for any custom made bike. I can have a custom made bike without reflectors or pedals or seat. Legal to do, legal to buy. They do say the state safety specifications are required to be followed though. There's a list of exemptions on their website.
You can argue about bits and bobs if you want. I'm okay having a debate about how a safe bike/ebike should be made. I won't, but I can see value in that discussion. Safety is a good thing. Maybe the CPSC and all 50 states should take on updating their safety specifications for the good of the consumer.
I believe the intent of HR727 which defined a compliant LSEB as a bicycle was to avoid all the subjective use parsing you keep bringing up. States can still regulate "use" of bikes but allowing a state to redefine products just opens to door to the nonsense you mentioned.
I think we are so very far apart on our interpretations it's best to just let it go. I can hope the CPSC preempts and you can hope they don't. One of us has to be wrong. You should read Court Rye's opinion on this in the EBR forums as he agrees entirely with me and he is around people in the industry all the time.