Well there are so many rules and official norms (approx. 400,000) and exceptions about pretty much anything in France that this is pretty accurate... Just look up the rules of the road regarding phone calls while driving for examples and see how it has evolved over time: specifically holding the phone was forbidden but using headphones were explicitly allowed until the latter also got banned by another law a few years back. Now to have calls we must put our phones on speakers (but not too loud) and use both hands for driving, effectively forbidding us to give any calls while driving all that without explicitly saying so.

It's hardly enforceable, but wait until you encounter a zealous police agent that's been tasked to give a certain amount of tickets