For the cars it is different story for a bunch of reasons.
I think I agree with your point, although I think there is reason to draw the line (that distinguishes) differently.
Due the the lack of outcry about acoustic bicycles (and I know there is some in specific places - say New York City, and maybe Sydney) I don't see licensing bicyclists generally - although if the evidence is actually there, I can be persuaded. But I want to see the evidence.
I do agree that anyone who has otherwise gained their road license can face the penalty for not keeping their word - even if they are on an acoustic bicycle. How much we should invest in this is a separate discussion - show me the evidence.
I do propose that a sensible way to reduce problems from ebikes
in public spaces is to require a road license to use an ebike
in public spaces. The road license is about maturity - by your signature you pledge to police your own behavior. I see this as an existing, low cost, widely understood way we already have serious investment in to weed out riders we can't trust to handle a powerful machine. Even the 250w machines are powerful.
If the evidence supports it, I'd consider exempting the 'class 1' ebikes, although not all jurisdictions make this distinction. But I would maintain the minimum age - that's about maturity in all cases, and need.
I think the errors from this approach
are less than the errors from other approaches. Pointing out that it is not perfect isn't a useful argument - perfect is not available and we can not waste time on that.
I don't see any substantial benefit for giving powered vehicles to children, apart from those who happen to be children as well as disabled. Children by definition are not mature, and their health is improved by using their bodies. Adults who give powered vehicles to children are not thinking straight about the child's welfare. Show me the evidence - I've seen plenty of articles quoting opinions from health professionals about this point already, and they are quite in agreement.
Children can ride acoustic bicycles. There is no compelling harm done by that. Let them have the benefits of using their bodies while those bodies need to grow.