Also, the French Army mutinied in 1917 (the Brits and Yanks basically saved their skittles) and hadn’t truly recovered by 1940.
Mutiny did not affect the entire army in that area. And it came at the end of about a 3 1/2 year static meat grinder that nobody could even imagine before WWI, and after it became obvious that no leader anywhere had a plan besides turn eastern France into a moonscape A half million French soldiers went missing in action. On those battlefields that means shattered into thousands of pieces by artillery and buried under a rain of mud.