If that isn't practical then surely you adjust the process - i.e. you witness the armourer showing you it's safe along with the AD.
It does seem ridiculous as a general point that firearms are treated as some mythical thing that it would be unreasonable for an actor to be trained to use competently and handle safely, especially given the amount of training actors go through in other areas. I think for plenty of people with some familiarity of firearms it just seems beyond the pale that you could have one in your hand and not know for sure what state it is in and then go ahead and point it at someone/pull the trigger.
I mean if we took a more common area like driving a car, would we think it was reckless for an actor to drive a car on a movie set if he or she didn't have a driving license/hadn't been trained to competently and safely operate a car.
It doens't seem like it is necessarily that slack in other productions, according to various posts on social media from movie industry people weapons safety should be a concern for everyone, actors should be shown a firearm is safe not just take someone's word for it (see comments form local 44 members etc..). Several people were to blame here, all three failed to ensure that weapon was safe.
This seems relevant too: