if hypothetically one could ban cars from cities and only allow such low powered transport, it would be quite an efficient safe and clean form of transport
I don't know, I'm not sure they are really solving something. Local residents can probably rely on public transports/walking/cycling to move within the city. People from outside probably need a car to reach the city itself, but if you can't use those low powered cars on high speed roads then there's no point in having one. Better a "full" car that gets you to a public transports node on the edge of the city and then you switch.