Yes, The responsibility falls on you to handle a gun safely. And the same goes for chain saws and any other tool that poses a hazard.
Baldwin is no more singled out than anybody else. And any of the millions of yahoos would be held liable if they killed someone after being handed a gun.
There are degrees of liability in a case like this and it’s going to spill down from the armorer first and then the person who said the gun was “cold”. Gun safety isn’t rocket science and people make mistakes all the time. Redundancy is the best part of safety procedures. The more people involved the better the chances are that a mistake is caught.
I’ve personally seen the most senior of airline pilots who were absolutely anal about safety procedures make a mistake that could have gone really bad. I’ve made some stupid mistakes in my life that I am eternally grateful didn’t end badly. Most people would embrace the actions of another who stopped a bad mistake from happening.
In Baldwin’s case imagine a safety protocol where the gun is demonstrated to the entire crew that it is safe to use. It could be done in less than a minute so it’s not going to impact the movie financially. Any member of the crew could have said one of the cartridges looks different and caught the mistake.