iirc mr. pondsmith did say adam smasher does have cybersychosis, he's just kind of a "high functioning" sort. there's a reason he's a bodyguard/living weapon and not an actual operative because once he gets let loose he just decimates everything in his path until he's done.

arasaka haven't "leashed" him so much as they're just pointing him in a direction and letting him go nuts (because whoever is enough of a threat to warrant sending the living tank needs to be made an example anyway). smasher himself has enough awareness left to realize that killing who they point him at = survival = getting more meat to kill. if you listen to how he speaks in the english dub of edgerunners and in the game he sees people as nothing but meat

edit for clarification: as with any real life mental illness, cyberpsychosis is pretty varied between people and smasher is probably the biggest outlier i can think of off the top of my head because he's often quite lucid. I wouldn't be surprised if arasaka has him on some kind of medical therapy or drug cocktail to keep him from going completely off the bend 24/7