Him being listened to by the general staff and thus, their formulating an effective counter-strategy for blitzkrieg are two different things.
Barring Marty Macfly coming back to Paris in 1938 with objective proof
that Hitler would NOT ever stop and French mobile-warfare doctrine sucked eggs, it would be very difficult for somebody to get the French to realize sitting behind the Maginot Line wouldn't work.
A POD I've flogged a bit is that official French participation in the Spanish Civil War would have been a nice laboratory for France to learn what works and doesn't in combined arms warfare. It was politically near impossible, even with leon Blum's Popular Front government.
I must confess as an American, I'm dirt ignorant of the politics within the 1930's French Army.
From what paltry readings I've done on the spin-up to WWII featuring the French Army- the civilian political situation resembles the current American one. The right and left thumb-wrestled for power and thought compromise a bitter surrender, not a political necessity.
FWIW, they did approve a rearmament scheme from 1936 on that delivered some excellent weapons to the French Army and Armee de'l'Aire.
The major weakness was in the tactics and strategy of the French Army hoping conscription, elan, improvisation, and the Maginot Line would carry the day instead of mobile, combined-arms warfare (and a defense-in-depth strategy) against Germany.
Changing that would need butterflies back to the early 1930's where instead of refighting WW1 with more modern weapons, they bought into a more technocratic, mobile, combined-arms idea of warfare. If they had done so, organized their forces and trained appropriately, they'd have been able to confront Hitler in 1938 a lot more confidently.