If you also take into account the time you spend at an airport and the possible slowdown from the wind (900km/h is airspeed) while having a theoretical but technically feasible 450km/h high speed train as well as the time it takes to go to and from airports (you can put train stations downtown and near public transport) you can actually achieve parity in most situations, or near parity in others
I've taken night trains and have liked them. But for a lot of business setting people would rather take an early morning flight than lose a night with family.
