Over here in France there's such a law too, but from my 2005 car, I cannot hear that noise. I barely hear the loud motorcycles behind me too, FWIW. When I hear them, they're usually up next to me.

When on foot, that's a different story. If there's low to no traffic, having an electric sneak up on you can be destabilizing.

Then again, I also ride motorcycles and remember one day, in a quiet neighborhood, there were three people walking in the middle of the street for some reason and didn't hear my bike, which was loader than the artificial electric car noise. They weren't wearing headphones, and given the time of day were probably not drunk either.