The fact that people so desperately want Baldwin imprisoned

Baldwin was instructed by the director to aim the gun at the camera and fire, as some sort of POV shot. Who sits behind the camera? The DP and the director. This is why they were shot. Baldwin was not just fooling around with a gun he knew was loaded and aimed it crewmembers as a joke. He was DIRECTED to aim the gun at the DP, more or less, and fire. He was INSTRUCTED that the gun had a blank.

I'm also not sure what your "hot gun" link is supposed to prove, he also called it a "cold gun", as confirmed off-camera by the assistant armorer, moments before the gun fired. He said "who handed me a hot gun" because, well, who WOULDN'T say that?

You seem to be completely denying the fact that Baldwin is an actor, the absolute lowest on the totem pole for safety. He was handed a loaded weapon that the head armorer, assistant armorer, assistant director, and director all said was completely safe. Sure, he probably should've checked, but that isn't his job. He listened to FOUR professional safety coordinators who didn't do their job, and now he takes the blame for someone's death?

Imagine if you were driving a race car on a controlled course that FOUR other "safety professionals" told you the car was perfectly safe to drive, but then the brakes failed and you killed an innocent pedestrian. Let's assume you know NOTHING about cars and it was not your job to inspect the car's brakes. Turns out the FOUR people above you didn't even attempt to do their jobs and blatantly lied because they were lazy, arrogant, and stoned on marijuana. But then, the mainstream public says it was your job to do a full maintenance check on the vehicle, while the four people above you who shrugged the brakes off escape criticism. How would you feel? Probably guilty about the whole thing, but you'd be asking people to look into safety professionals who failed to even try.

If he had complied with the most basic gun handling safety requirement, he would not have killed anyone.

The person who put the bullet in the gun, Hannah Gutierrez-Reed, and her boss, David Halls, who negligently mixed live ammo with blank rounds.

The shooter is always responsible for the bullets they fire.

I sure hope so. Imagine the alternate timeline where De Niro blew his brains out by accident because the armorer put a live bullet in the gun.

I can imagine that the guns on the set of The Deer Hunter were carefully checked, but I have not seen any behind the scenes footage.

Were those functioning firearms? Baldwin was using an actual firearm that was supposed to be unloaded or loaded with blanks, etc. Unless the script calls for an actual firearm to show a projectile exiting the barrel, there is no reason to use a functioning firearm on the set.

It is not difficult to deactivate a revolver so it will not be capable of using live cartridges. The cylinder can be modified so that standard ammunition will not fit, but only dummy cartridges or cartridges with a primer to make a popping sound. The barrel can also be partially obstructed so that a muzzle flash can be seen, but no significant projectile or debris will exit and be a hazard for anyone that the prop is pointed at. Normally, shooting with an obstructed barrel is dangerous, but this is the usual method with blanks, especially if a semi-auto or fully automatic firearm is used. This is why an expert armorer is required to be on set and supervising the firearms all of the time. Producers (like Baldwin) need to ensure this is happening.

Gunplay on film sets normally appears to be rather fake. This is obvious to anyone with experience shooting actual firearms. The sound is not accurate; it is no where near loud enough. There is little to no recoil as blanks firing only gun powder and a wax or cardboard wad are far lighter than an actual lead bullet. In the end the producer normally is satisfied with editing the sound to make the gun appear be at an acceptable level and they will use blanks or CGI if they want a muzzle flash.