I read the TOI report. Its 1hr 30 mins for lko and 2h 30 mins for bsb approx. While the cost for economy seats through flights is same as that of a possible bullet train, you need to take into account the time taken to board the flight and depart the airport at destination which approx takes around 90 mins on normal days. If anything, i would say that bullet will cover the distance in less total time.