A port, a mine, a rail yard or a disaster response deployment has the same shape of problem: coverage the public network does not provide, control the public network does not offer, and a site that may extend past where terrestrial infrastructure reaches.
It also already has Wi-Fi, probably has some low-power sensors, and needs cellular for the things that move. Deploying a private 5G network alongside those creates a fourth network to operate rather than solving the problem.
This platform carries all of them under one management plane, with non-terrestrial links available for the parts of the site terrestrial coverage does not reach. The deployable form factor matters more than it sounds: many of the sites that most need a private network are exactly the ones where fixed infrastructure cannot be justified.