Well, there's still the infrastructure to actually distribute the drones to where they're deployed.
So if I can use cruise missiles to take out your air defenses, and long range bombers to take out your airfields, and then start hitting supply caches and truck convoys, you might have a hard time actually getting the drones to the areas where they're needed before their targets have moved on.

Or not, I don't know. I'm just curious how it pans out in a more asymetric conflict.