ariIt takes a special kind of train company (i.e. #DeutscheBahn) to advertise a 149 km/h service as highest of high speed rail: Frankfurt - Hannover non stop, 338 km in 2h16. Actual averages will be even lower due to delays.
The fastest conceivable conventional rail (accelerate to 160 km/h at 0.5m/s², hold 160 steady, decelerate) would beat it by 9 min.