Robots hitting robots is actually an interesting idea. I’m watching the robot clubs in every high school build fighters and robots that compete in robot challenges. Humans model out there evolutionary survival of the fittest in every aspect. Evolution is happening right now everywhere and we are the fuel behind the rapid advancement of AI and Robots. When we hit our limits and they start building themselves at scale, we will be lost.
The important thing is to not give them any incentives. Then the scale will always be in our control.