Why put his life in jeopardy if someone clearly under the influence of drugs is raising a weapon toward him?

Whether you're a trained martial artist doesn't matter if you're hit over the head with a weapon or a knife is rammed into an artery. It's one thing fighting in a cage or rolling on the mats where you can tap and there's help two steps away. It's another to physically engage with a meth head with a weapon who just broke into your home in a wrecked room with no space to move, knowing they're desperate and won't think twice about ending your life. This also isn't Ryan Hall or Matt Serra taking down stupid drunk man in a well-lit restaurant with people surrounding you and a first-aid kit to the side.

The bravado of the gym, octagon, and internet aren't worth your life. When your life is literally at risk, use your head, make good decisions, and don't let ego let you get more than a few feet from an armed meth head who just broke into your house and will kill you without knowing what's going on.