Such statements aren't usually wrong. Some superfast mass mover will exist on the ground. MagLev, or Hyperloop, or what-have you. Keep in mind, when poeple said, e.g. Da Vinci's ornithopter thing would never fly, they really meant heavier than air flight. And ewhile we got heavier than air flight, and his ornithopter can now be buitl, we primarily use planes or helicopters. The few ornithopters are built as toys. Likewise, while we may eventually be able to build a hyperloop, it seems likely that mag leve will beat it as super-fast people mover.
The statemnts that are normally wrong are theings where no competitor obviates the need before the technology matures.