Someone travelling to France from abroad could always tick the "motif familial impérieux" and then go from the airport to his home without any problem. You are always entitled to go back to your home country.

Travelling from your home to the airport to begin a tourism itinerary is really something different and not covered by the attestation.

Regarding the controls, you may or not may be controlled. But if you are, you risk a fine and loosing your ticket. That's how it is. Regarding the rules, they are no different if going from Paris to CDG to board a flight to Cancun or to the Gare de Lyon to catch a train to Marseille. I'm sure most people won't be controlled, but it does not mean that it will never be the case.

Why isn't the international travel question not covered by the decree ? Because the government knows perfectly that it's illegal to forbid it's citizens to leave the country. So they are happy that the "déplacement dérogatoire" don't even allow you to go to the airport without a compelling reason.

Really hope that someone denied at an airport border will raise this issue to a court, so we will have a clear answer. Since, what's sure is that we will never have a clear answer on whether the controls are enforced or not.