The benefit at least in Germany is for commuters. My monthly pass went from costing over 150€ to 49€ as I had to pass through two transit agencies to get from my home to work. The fact that every transit company sets their own fares and doesn’t cooperate with neighbouring companies is fully irrelevant now to the joys of many.
I don’t know if France is structured the same way, or if the plan of this is also to include local transport, but the Deutschlandticket is saving me a lot of money and headache.