If you steer your 3 ton SUV around a corner and suddenly find yourself facing off a mother pushing her stroller across...or if you´re on the Autobahn and round the bend, there´s the tail end of a traffic jam...reaction speed is what makes the difference between "holy shit" and "that´s it".
By the way, there ARE aspects of operating a motorvehicle on public roads that would warrant regular refreshers at all ages, like first aid or keeping up with the ever changing traffic laws. And I´d be totally up for that. But that´s another discussion.
Oh and ask me about mandatory basic child health and safety courses for soon to be parents. Yes, I have lots of opinions ;-)