Yep. You're right. It's really just nav blocking that's killing the drones. I wonder if there's a way to have these drones operate without a need for GPS. Instead, use cameras to read terrain and map that against the known terrain...
But it has to be a question of cost too. Drones are attritable by their nature and there may be no more reason to try to recover one than you would recover a discharged bullet.
A bigger upset is loss of communications, very few if any drones operate autonomously currently, and if there is loss of communications they may try to return to base. Off course it is more difficult to jam line of sight or drone to satellite communications than GPS.
I wonder if either or both sides are patching this out of software - otherwise, communications jamming becomes a quick way to make the drone lead the enemy straight to your base.