The solution to city air pollution is a different vehicle with a different drive train: an EV. The C15 is a workhorse for farmers and craftsmen not for shopping trips and driving the family to visit granny on the other side of town.
EVs are still heavier than ICE vehicles and will for the next 10-20 years unless one is OK with a tiny battery. And heavy weight means more pollution from wheels that produce particles that ends up in lungs. Note brakes also pollutes with asbestos but EVs typically have regenerative braking so I think brakes pollutes roughly the same in a heavier EV as in ICE car.
> The solution to city air pollution is a different vehicle with a different drive train: an EV.
Priority list should basically be:
0. Bicycles 1. Metro 2. Buses 3. EVs
(not counting emergency and service vehicles)