General Discussion

...a fatal crash on a scooter.
Even if these were regulated to 35mph max, that doesn't make them safe.
I knew a guy, 2 months after he retired, was bike riding when a driver opened his door to get out.
Unfortunately, that was just when the retiree was going around the car.
Hit the door, went flying. Died of head & neck injuries.
This guy was in his mid 60s & wasn't a Tour de France candidate. Perhaps he was going 20mph. Still enough to cause fatal injuries.
If I were going to regulate these, I'd set the max at 15.
Realistically, nobody that has one of these convenience cycles needs to go faster than a modest bicycle ride.