[oneplane]

Already a thing (mostly remote controlled drone ships). But you'll always need mitigating controls for unexpected or low frequency events, and it's not always feasible to fly in a crew at which point the crew needs to be on board. This effectively is the same as the crew that's already there right now, so it doesn't actually impact all that much.

The biggest benefit of remote, drone or automated piloting is the way you could make better use of a person's time, and maybe save a tiny amount of wages, but it's mostly the resulting functionality/features/business processes that is the benefit, not the headcount cost.