Earlier quoted context omitted.
> The sane environmental stuff you mentioned has morphed into a requirement for deeply integrated electronic oversight Decent catalytic converters require an array of sensors, ECU, and ability to fine control the engine inputs to work - without them most large cities would become smog ridden hells.
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.
Priority list should basically be:
0. Bicycles 1. Metro 2. Buses 3. EVs
(not counting emergency and service vehicles)