All you really said in that quote is "they're not covering the same stuff". But you haven't said what it is. Pretty much everything you said comes from the marketing used by the combatives programs. It's good marketing, and I think the folks who wrote it believe what they said. I also know it's not quite as true as they thought.
Its more of a neuance. Let me run off some comparisions. if we comapre a comabtives programe to TMA, it covers diffrent things on merit it doest do kata. If we comapre it to a striking or grappling only system, it covers diffrent things as its a hybrid. the scope is meant to be for real life fighting in what ever context so its not comparible with combat sports 1:1 as thats where the nuance should change, but it has more in common with combat sports.
I dont mean something like, the punch is diffrent, but more like there isnt as much fluff around the punch as is the case in some systems and application is more based on what you should do in real life not in a ring. This is the literal interpritation of combatives, as stated earlier RBSD has been coined by people as a marketing ploy and they dont teach good ssytems yet the orgininators of the term (to differentiate themselves from others) did/do good things.
I am also not relaying one is defacto better than the other, just that the term combative should be applied to things more focusing on fighting in reality that the term MA or combat sports or TMA etc doesnt cover, with that there is some blurred lines. And as with everythign there are those terrible systems that coin the term. I am in general not citing the "win every fight with these 4 simple moves" system/advertimseent, but the good ones.
If we look at the start i basically stated comabtives is the basics and as applied to real life and usually only covers the basics. (granted with exeptions and i belive several have added in more complex things for longevity) That doesnt seem like im misselling it or over grandising it. The model for learning in combatives tends to be inebtween showing up for classes and courses, you can get both or either done in the segment.
As for neuances,situational awareness, enviromental awareness, muiltiple attackers, weapons of oppertunity, carried weapons and adreline are the things that come to mind that these things would differ (if only slightly) in dealing with. I think i have explained my viewpoint on sport and how you dont need half of that to be good in a sport as its a sterile enviroment.
Is that a decent enough explination?
@drop bear Not a direct response to yours, but it at least a partial reply or one that seems relivent to your post.
Addendum: In my posts and ramblings about military hand to hand systems (comabtives systems). I have relayed some of the issues and how the scope of each changes. They generally are either for aggression or last ditch situations, usually a mixture of the two. In many places it just starts and ends at a bayonet course and sufficent training to run the course correctly.