not sure, in western Europe I take the bullet train even when the airplane is cheaper, because it's faster and more convenient. But of course the bullet train is generally only slightly more expensive, if we were talking 20x price difference, I might learn patience.
A second aspect of speed versus price, is that in airplane travel a lot of time is spent accessing the airports, going through security, waiting in the departure queue, etc. Offsetting those 3-5h with a faster travel time might prove challenging.
But I am happy to annonce that the French rail is catching up, they have started queuing up people in the station to check the tickets before boarding, requiring clients to arrive 20 minutes early, making smaller seats, removing the bars, and building the new train stations in the outskirts with a crappy connection to downtown. Progress!
A second aspect of speed versus price, is that in airplane travel a lot of time is spent accessing the airports, going through security, waiting in the departure queue, etc. Offsetting those 3-5h with a faster travel time might prove challenging.