A very good point.Personally I think we are all too hell bent on the evils of CO2 and tend to forget there are far more harmful things that come out of the exhaust pipe of an ICE
Vehicles started using diesel engines over 90 years ago and its only recently manufacturers moved to using AdBlue to try to clean up their act, the majority on the roads today cannot use it so it'll be years before these polluting vehicles are taken off the road, old diesel cars, trucks, busses, trains and ships will continue to spew out these nasties for the foreseeable future.