The difference with diesel engines is the particulates they output are very small and cannot be effectively filtered by the lungs. As a consequence they are far more hazardous to health than emissions from a petrol engine. To effectively filter them will massively reduce the performance of the engine, which is why the car manufacturers were lying about their emissions figures, something that has now brought the whole matter to a head.
There is unlikely to be a blanket ban on any type of engine however I think it is very likely that production of diesel engine cars will cease entirely within the next ten years.
Current Lash Up:
TEAC VRDS 701T > Sony TAE1000ESD > Krell KSA50S > Troels Gravesen Faital 3WC-15.