It’s important to remember that the lore books are intended to be tinged as propaganda by the narrator. Of course the imperium will say it’s angels of death are semi-gods of the battlefield, but in reality armor only stops so much and a 7ft tall slab muscle walking tank is impressive, but a carnifex is still gonna carry its weight on the field as well and fuck up some astartes
My work had something like this to detect drug usage on premises for a while (it was and is a problem still) and it costed like 30k capital and 2-3 opex a year. We had it for like a year and only took it out because there were too many false flags and security didn’t and doesn’t have the staff to be chasing down every alert anyway.
It was neat that on paper it was able to detect different drugs, heroin, weed, meth all flagged different alerts with 2 of those contacting police when detected. Unfortunately it was only like 70% accurate and we didn’t/don’t have enough security staff to use it properly so it’s gone now.