Trains don't operate from door to door. The last mile problem persist, unless you travel between railway connected city centres. Not everyone lives anywhere near a railway station.
(I live in Europe which has relatively good railway network, still I prefer my Tesla as transport method.)
True, they also run such a trains here in Finland, an overnight trip from south to north (Lapland). The train tickets for our family of 5 plus a car are so expensive (total 1200 eur) compared to minimal marginal cost for using our EV (150 eur), that we always choose the car.
They were suggesting they want to use the same vehicle door to door with it being automated during the freeway bit. A train would still mean find some transport to the station, wait for the train, ride train, find transport from station.
(I live in Europe which has relatively good railway network, still I prefer my Tesla as transport method.)