I read the proposal. It argues for making the accelerator "heavier" when over the speed limit. For safety (and political) reasons the driver will have full control over the throttle at all times.
I would be happy if no one could speed under my windows. Difference between 50 kmh and 30 kmh is equivalent to 50% noise reduction (~ -5 dB). And tyre noise becomes dominant just a little over 30 kmh (20 mph).