I think the take away on this is:
As is, currently, actors are not responsible for checking their prop weapons on set. No actor is ever expected to do it, because there are people responsible for it. In the event of an incident, in the current standard practices, no one can reasonably blame the actor.
But, systematically, it shouldn't be that way.
We can't look at one incident and say "clearly the actor was in the wrong" because culturally, it's X Y and Z tech's job to check the firearm. But cultures within an industry can shift. Currently, firearm safety on set isn't everyone's job. But it should be everyone's job. The system should be better, because firearm safety is a demonstrably life-or-death process.
How do you change the system? By holding productions liable when stuff like this happens. You sue the absolute shit out of the producers, so the producers have a crippling fear of NOT improving the system.
You don't hold the actor Alec Baldwin responsible. You hold the producer Alec Baldwin responsible.
This is a false equivalence and you know it. Yes, it makes sense to put one person IN CHARGE of safety, but in a properly working system, safety is everyone's responsibility. Making only one person responsible for it creates a single point of failure, which is how accidents happen.
Yeah, being a firearms professional is not the actor's job. But it's absurd to say that the only thing an actor needs to know how to do is act. If a scene requires a character ride a bike, the actor needs to know how to do that. If a scene requires a character take a golf swing, the actor needs to be able to do that. They don't need to do so at a professional level, but they need to be able to do so enough to make it work for the camera, and more importantly, not hurt anyone.
The correct process is not difficult. When the firearm is handed off from the armorer to the actor, the armorer proves it's clear. Every time. The actor doesn't need to know how to clear a weapon, they just need to know that the armorer needs to clear it for them. If two people (the armor and the actor) are responsible for making sure its cleared every time it gets handed off, then it's harder for that step to get forgotten.