You can operate the drones without a connected device. Operator location is done by locating the radio source. It would be better to have repeaters and cable transmitter to them to avoid direct strike.
Tech people are usually paranoid by the most unlikely scenarios. A soldier with an antenna can pinpoint the operator location much easier than trying to get this kind of info from china without leaks.
Its not impossible that DJI could have failsafe phone home systems in there that'll still send info back home after rooting. My guess is that the products they produced before the Ukraine war were more naive and now that they've learnt consumer drones will be used in warzones no matter what, I'll bet they have started incorporating such failsafes. Imagine being able to know where every mavic in the frontlines are and selling that info to the Russians.
