My teenage nephew who has never had any tactical, SD training was attacked by a boar one morning... he had a empty rifle slung over his back and was able to put (2) rounds into the boar which ended the event. Later he stated that he never remembered loading. His level of training was basic safe operation of a firearm and hunting with his Dad.
I am 100% in support of training.. but the idea that people are somehow bumbling goofs under stress without specialized operator training, is just not reasonable.
Life is a web woven by necessity and chance...