This analogy is flawed. The engineer would be a gunsmith. The bridge collapsing would be the gun catastrophically failing. A bridge is not deliberately designed to inflict damage on animals (mostly humans) the way a gun is.

Getting a 404 error on that link.

No true Scotsman.

Pretty sure the law doesn't give a shit what conventions Hollywood has developed and followed over the years. You have a gun in your hand, you pull the trigger, you are responsible for the outcome. Don't like it? Learn gun safety, ignore what the person handing you the gun claims, check that it's unloaded yourself. Hollywood conventions need to change to align with reality.

Edit: I've been out of the loop. I wasn't aware they dropped charges against Baldwin. That's really fucked up in my opinion, as per the above.