The simplest solution is to let scooters have priority in the streets. Aggressively police the aggressive vehicle drivers that are pushing scooters onto walkways. Especially as the car drivers already have a license system.
Sure you might have the occasional delivery truck or car but it would generally be much safer and more pleasant for everyone.
It'd be quite ironic if the US pulls this off in their cities and European cities become car-infested urban jungles.