I like your idea of forcing sites selling airline tickets to be honest about their cost and delays, but… after the fiasco of cookie-warning pop-ups, that’s a particularly promising can of worms.

> if you're already arriving or leaving on a long distance flight, the whole overhead of getting to/from/through the airport disappears

About connecting flights: most major French airports have a high-speed train (TGV) station for that reason. They typically have fewer trains than central stations, but they have good connections to nearby cities with small regional airports.