Agree with you 100% on this. One of the vital stuff is the ability to take a punch/kick.This is also generally why TMA gets handled in MMA. Because they don't focus on a bunch of vital stuff that wins fights.
If I get punched 100 times on my head and still standing, when the 101 punch land on my head, the chance that I may still standing can be high. If I have never been punched on the head, the 1st punch may knock me down.
Too many TMA schools don't train full contact. That can be a major issue IMO.