I don't really agree with that. Helicopters can auto-rotate, drones can't. If something goes wrong with a drone system, it is going to crash hard guaranteed and likely doesn't have any meaningful control on the way down.
It's certainly not crazy to imagine that you could cut the costs of a helicopter-like aircraft that was purpose-made for relatively short, relatively low-speed, relatively light load duties.
The energy cost during operations is very relevant, too, which is why you see things like tilt rotor designs with wings/bodies to generate lift.
When Airbus was doing the math on these a few years ago, the pilot cost was also one of the main concerns, so it was "autonomous or bust", and they ended up investing a lot on the autonomous side (not just the aircraft but also urban traffic management, etc).
