As usual, the devil is in the details. These are drones, not nukes. Nukes have effects for miles away and are so powerful that their detonations cannot be shaped at all; whereas suicide-drones have to fly directly to their target and reach it intact.

The same amount of shaped-explosive that can crack a skull, can neutralize one of these drones. As such, the braindead countermeasure is to retarget these same drones at the stolen drones. At worst, the IFF radios might add a negligible amount of mass ... but that won't matter for long, because once the enemy knows you're deploying counterdrones, they'll need their own IFF radios in order to try to avoid your counterdrones. (Or the enemy could add armor to their drones, but that will make them massive/unmaneuverable enough that you can increase your counterdrones' explosive payload to penetrate their armor, while still being able to intercept them.)

If you're looking for historical analogy, try military aviation in general. During the first World War, bomber planes would have been game-changing ... if not that there were fighters, too. A slaughterbot is a bomber; a slaughterbot that seeks the enemy's slaughterbots is a fighter.