I mean... It's not the only problem? If you get killed by an actual bullet on a set something has gone spectacularly wrong. But you could just as easily get killed by something getting lodged in the barrel and getting propelled at bullet speed. Even a fairly small obstruction can be lethal. That's why whenever you as a props person / armorer hand a gun to an actor you perform a full check of the gun while the actor watches.

If you as an actor get handed a weapon without a check you call foul. If you as a crew member see a props person hand off without a check you call foul.

Even rubber prop weapons that have no capacity to fire and no internal components at all are treated the same as live weapons. Only props people or actors touch them, no one else. They are under lock and key when not actively under supervision or on someone's person and they have to be demonstrated, checked and explained at handoff with instructions for their safe return... Again... Rubber weapons on your average film set set is treated with more respect then the live weapons on Rust were.

It's really hard to explain to people how actually fucked up the situation on the Rust set is because they think we're wild westing all the time.