I don’t know how common it is in France, but you can ferment a baguette for 3 days and it makes a big difference.

Long fermentation with little sourdough is making a come back in France (e.g the Respectus Panis thing) but I would think it's harder to apply to baguettes for professional bakers looking at how many they churn a day. That would be a lot of proofing bread to store.