brains can be hacked too at any given moment.
Maybe, maybe not. Brainwaves & genetics operate on scientific/physical principles & laws (even if barely anyone if anyone knows the sets of laws at this point). T'is possible the bodies have their own inbuilt permissions systems, such that certain levels of access could only be granted in accordance to the sets of Laws whereby permission is either consciously granted or determined according to adherence of principles protecting against abuse/manipulation.
They will live in fear 24/7.
Anyone in the base Survival state of consciousness does live in fear 24/7. However, there are likely to be certain technologies available soon enough to facilitate in switching out of survival state...