Paris CDG and Lyon LYS are the only airports in France I can think of with a built-in mainline train station. And the schedules are much less convenient than those in city-centre stations.
But I suppose the majority of overseas travelers coming into France by air with the intention of connecting to a smaller city do so via Paris or Lyon. As European travelers seem to enter by car or go directly to their destination. At least that’s my impression from reading a few articles about tourism in France.
https://en.wikipedia.org/wiki/Category:Airport_railway_stati...
But I suppose the majority of overseas travelers coming into France by air with the intention of connecting to a smaller city do so via Paris or Lyon. As European travelers seem to enter by car or go directly to their destination. At least that’s my impression from reading a few articles about tourism in France.