Gave you a like.I would argue that actually indicates the opposite. If you and I play poker for the first time in our lives... and whoever loses the hand dies... after one of us dies the other person isn't going to be particularly great at poker. The surviving person will still have only played poker once in their lives.
The reason martial arts have progressed is the precise opposite... the scientific method applied and techniques done repeatedly towards perfection. Now instead of dying on the battlefield I could go 100% on the mat and see exactly what works, what doesn't, right up until a simulated death (tapping). That's the scientific method and will guarantee the best results.
Teleport a BJJ black belt vs any guy on these battlefields from 1000 years ago, and take a guess at what happens in a one-on-one unarmed fight to the death.