From what I can piece together from the short clip and comments, this is more the fault of poor communication than "concealed carry/gun nut culture."
- Apparently the female deputy had given him permission to support until a second deputy arrived? Was dispatch informed? Did the second deputy know?
- Was he disarmed at the time he was shot? It looked like she grabbed the gun away.
- Who shouted "he's got a gun in his hand pointing at people?" Part of what got the dude shot, I think. On-site swatting.
- Apparently the female deputy had given him permission to support until a second deputy arrived? Was dispatch informed? Did the second deputy know?
- Was he disarmed at the time he was shot? It looked like she grabbed the gun away.
- Who shouted "he's got a gun in his hand pointing at people?" Part of what got the dude shot, I think. On-site swatting.