I wouldn't bet that it would not become law. There are already plans to outlaw classic cars as they are too polluting and uneconomical, our roads and cities are becoming toll controlled to remove cars from them and most of the race tracks are noise limited to the point of closure. The green band wagon has a heck of a pace over here and policies are being put in place for fashionable reasons rather than purely environmental.
Remember that the EU passed a law that bananas had to have a specific curvature
Prius are a joke, a 1.0l diesel city car will do 60-80mpg, another fashion item