I was loosely involved in some research for auto-navigation (unsupervised pathfinding) using quad drones. As you can see, they're clumsy. They're also loud, and louder with payload. Jamming won't affect a completely autonomous drone, as you stated. There's a lot of military money being poured into this kind of AI research because it can, in theory, minimize collateral damage by getting very close to the target -- basically flying assassins.