When the gasoline powered carriage replaced horses the only thing they were meant to replace was horses.
I disagree with this premise because it ignores too many things.
Self-powered cars had two primary effects: they reduced the huge amount of effluvia that horses generated, and enabled a single person to cover more miles with more cargo in less time.
By moving to self-powered cars, you need fewer
- * horse handlers, such as veterinarians, stable hands, leather workers, etc
- * waste haulers to clean up after the horses -- during the horse-and-buggy era city streets were awash in horse-generated efluvia, and they posed a significant environmental problem
- * drivers, as a single driver (your "augmented person") can cover more distance with more cargo, in less time, than a team of horses can.
The primary reason to move away from horses was expense, and the thing that makes horses expensive is paying for people. The move was entirely driven by a reduction in work force. The fact that a single person was augmented is what makes it cost-effective; the same principle applies now because a single person can operate an entire factory floor -- it's no different than before, a single person's abilities have been augmented by technology.