That assumes that war will "evolve" into drone vs. drone. I don't think it will. Sure, drones will be used more and more, but there will always be people involved, even if they are "merely" civilians who get caught in the crossfire.
Most wars aren't fought in completely uninhabited areas. Drones will always have people to kill, and their controllers will always aim them at people.
You can't assume what you want, the facts on the ground are clear, we are moving to drones, AI, robots. And the nations who don't move that direction will not have a chance to fight any war due to the asymmetry in the cost. It would be like fighting guns with arrows.
Regarding the second point, UAE had 2400 projectiles on them with 10 causalities. This is a war of economies, not aim for people. So your second point doesn't also hold on the ground given the current systems let alone the system 50 years from now.
Most wars aren't fought in completely uninhabited areas. Drones will always have people to kill, and their controllers will always aim them at people.