It was the French Prime Minister that lost France, not the French Army.
Reynaud phoned Churchill in the middle of May blabbering that France is lost.....so he'd given up by then, and had he allowed Gamelin's attack from the north to meet up with an attack from the south to cut of the German bulge, things "may" have been different.....instead he sacked Gamelin and replaced him with Weygand who's first priority was to get a good nights sleep and then have a jolly around Paris for a few days.........2 days the French and Allies couldn't afford to loose.
Even the Germans couldn't believe their luck in the Battle of France, many wrote afterwards that it could have been so different given the French and allied superiority in artillery and parity in all but aircraft numbers, and it was the effectiveness of the Luftwaffe/Army Blitzkrieg tactic that gave them that extra edge in a short time.
Mind you, my Uncle went to France with the BEF in 1939, and was one of the lucky ones to be evacuated at Dunkirk in 1940, and he never had much of a good word to say about the French army - he thought they were scruffy, smelly and ill disciplined......but he was a pre-war regular, and ended up doing 22 years and finishing up as a WO2 by time he retired in 1959.