There have been nearly 2 million gun deaths in America during the last 30 years, and one gun death in a Hollywood production. Even one gun death is too many, but 2 million is way, way too many. For the most part, Hollywood productions have an excellent record with guns, that are not matched by regular gun owners. In other words, no one cares what regular gun owners want to lecture Hollywood on gun safety. Hollywood has a good system, and should keep applying it.
That means that in a Hollywood production, the person handling the gun is not responsible for the gun. It is the armorer's responsibility to make sure all guns are safe. It actually is dangerous for actors to mess with guns by checking them. Actors are supposed to act, and the armorer is supposed to take care of gun safety.
It is completely reasonable for a cinematographer and director to be looking down a camera at a gun pointed at them. It happens often in Hollywood productions.
The armorer did a terrible job. She allowed loaded guns to be confused with unloaded guns. She had loaded guns on a set that was supposed to have no loaded guns. The revolver in question was not properly maintained, which would not have mattered if there were never any ammo put in it, but there clearly was. She was apparently passing the time by shooting the prop guns at cans, and did not care enough to make sure the bullets were all accounted for.
All evidence points to some level of negligence. That is as far as you can get from deliberate. Given the lack of responsibility by Baldwin, it will be hard to get him on any crime. Murder cannot happen without intent. You might be able to get negligent manslaughter against the armorer... But that is a stretch.
Then there is the civil suit. Clearly the armorer is negligent, but there also seems to be a culture of not caring about safety on the set. Baldwin could easily be sucked into that, and even more easily the non fatally injured director Joel Souza. This is a workplace accident, not a murder.