In this case I think the approach taken by the US is better -- set aggressive fuel economy standards and let the market either

a.) figure out new technologies for much better fuel economy

b.) figure out electric vehicles are cheaper

My point here specifically is not that the numbers the US chose are correct (let that be for another debate), but that this method of effectively restricting/"banning" gasoline cars is better for everyone. https://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy...