many jurisdictions label more-than-3-wheels as "motorcycles", even with no motor on 'em, because that allows them to abuse the population's potential.
Think how much use a 4-wheel bicycle-car could be, in event of no-available-fuel, to a farmer:
they could get stuff to the local market, instead of throwing it away.
Or, if a dairy farmer, they could get emergency-people to their farm, to help, instead of just killing their entire herd.
Bureaucratic-authority won't tolerate autonomy.
They'll NEVER allow the law to be based on something sane, like whether it's a human-powered-vehicle, instead of the idiotic "number of wheels it has", law.
Integrity in legislation is faaar too much to ask, of legislators.
Ask that state which reinstated an anti-abortion law from the 1800's, if integrity ought be permitted to interfere with their authority..