Personal experience has shown that to be far from absolute.
I spent years practicing martial arts, kempo, blade arts, etc. I also spent nearly thirty years dealing with chaos. All of that lead me to one stark conclusion. Martial arts are great. Guns are great. Knowledge, skill and experience are all vital building blocks. However, one thing stands above it all: be decisive and willing.
If you think a gun is a cure all it is, only if you're willing to use it. If not you've likely provided your opponent with a nice alternative. If you think your chop socky skills put you a step ahead, that's fine until someone who isn't as impressed as you are is bouncing your head off the concrete.
I've seen cops who approached BJJ as if it were a religion, like some here seem to, get their heads handed to them by someone who didn't know anything, but were just junkyard dog mean and didn't hesitate. All they wanted to do was cause pain and damage, and weren't bothered by the thought of taking some themselves in order to get it done.
I always came out ahead working the road because I was decisive and wouldn't hesitate. I preached that to recruits when I was an instructor. Quite frankly, I've never had a problem with hurting other people, I was just smart enough to stay within the law while I was doing it. I ran into more than one individual half my age who thought they were the second coming of Chuck Lidell, until they found out world isn't the gym. You don't "roll" in the world.
You break things and hurt people before they do it to you.