So if you buy a lawnmower and use it for your business to cut your neighbor's grass (instead of tearing it apart by hand), that should be illegal? You've used a capital investment to increase your productivity. Your productivity gains have driven anyone using a less efficient method out of the market.
What if it's a robot lawnmower instead of a push mower?
What if you and your neighbors pooled in some money to buy the robot lawnmowers?
I think they could have worded it better. I think they were saying that profiting from the labor of others is unethical. Using robots isn't unethical because you're not profiting from something that needs the income for itself. And it isn't really "working". Working requires expenditure of limited time and resources, which robots either of unlimited of, or is provided by the owner.
What if it's a robot lawnmower instead of a push mower?
What if you and your neighbors pooled in some money to buy the robot lawnmowers?
What level of indirect management is unethical?