Sourdough/pain au levain never really went away in France, Poilâne's sourdough culture dates back to the bakery's founding in the 1930's. When Bernard Clayton traveled around France in the 60's and 70's doing research for his Breads of France book, he found a lot of small town bakeries that had sourdough cultures that dated back even further.
But there have been several cycles between good bread and cheap bread since WW2 in France, especially in Paris. Prof. Calvel was widely credited with saving French bread from sinking below mediocrity in the 50's. Looks like it's swinging back towards good bread again.
SAF is a French company, though it has facilities in several countries.