The french greens appear to be objecting to the changes in the measure since its proposal for this reason. From the article, the original proposal was four hours and by reducing into 2.5 hours you've got out a lot of flights which people would seriously consider taking rather than going by rail. Even as someone who happily shows up for European flights with 40 minutes to go, if I could take a train rather than go through airport security for a trip under 2.5 hours I think I'd rather take the train.