1. Cut all the power (grid connections A, B and C, disable generators) - nobody says no if you ask nicely and have a big gun 2. Watch the special teams struggle helplessly to hack into offline systems 3.PROFIT!!!

Your assumption (that the network somehow runs on unicorn farts and that the need for boots-on-the-ground protection is obsolete) is fatally flawed. There's no way to outcloud everything, no matter how vigorously you try to handwave away the physical layer. Someone needs to keep the juice flowing, which also needs physical protection.