Utter bollocks, with more holes in it than the Moon. The Maginot Line was a barrier opposite the German frontier to economise on manpower, France having a much smaller population than Germany. Men in fortifications had the effect of seven men in the open, which allowed the French to plan for a war in Belgium rather than France in a narrow area where the other part of the French army, armoured and motorised, could fight a bigger German army.

See
https://en.wikipedia.org/wiki/French_war_planning_1920%E2%80%931940


The Seeds of Disaster: The Development of French Army Doctrine, 1919-39 (2014) by Robert A. Doughty


British Rearmament and the Treasury, 1932-39 (1979) by G. C. Peden