If it became a reality my guess would be it will look like the FF14 market or Steam Trading cards. Everyone undercuts the fuck out of each other so they can sell the old games until finally you can basically buy anything you want for pennies.
I see this going one of two ways. Either Steam wins on appeal or they pull out of the French market along. It would also push the industry much faster into the SaaS territory they've been masturbating over for a while now.