Disputes between martial artists are like disputes between academics. It's as though a geology professor in Montana were to declare exclusive purview over the entire field, and declare those credentialed professors at other institutes of higher learning to be unqualified in the discipline all have studied from the same sources. Outside a narrow group of initiates in the field, does anyone take that seriously or even care?
At best titles reflect achievement; our society is a meritocracy, where pieces of paper declare worth. At worst they feed the ego, all too often poisoning a person's self-inflated sense of importance. Introducing oneself as a grandmaster might raise an eyebrow in an elevator, as much because of the esoteric reputation it connotes than any real appreciation. It's no different than a lawyer introducing himself as a senior partner in some law firm of which you've never heard. You may appreciate the long climb it took to reach such a position, but even if you are interested in services offered, which will probably be a narrow field of specialized expertise, you would probably be wondering how much coin he would charge, and in reality much of the work on your behalf would be done by much less exalted, and certainly less expensive, low-level "associates" grinding their way through the corporate hierarchy.
When I was starting my journey in martial arts nearly half a century ago, actual grandmasters were as common as real dragons. If you were to meet one, it would probably be at a distance. Even if it was in a seminar, the actual hands-on mentoring would almost undoubtedly be from lower ranking instructors. That may be less true nowadays, especially in some arts, but that is because rank, like the dollar, has inflated. I can meet more grandmasters at a party now than I encountered in my first 30 years on the mat. Does this somehow diminish the value of what was learned from those other teachers? Certainly not. If anything, without developing a background and depth, encounters with the higher ranks would be no more significant than that introduction in an elevator.
My Tai Chi teacher, the late John Wong, held rank of 5th degree or higher in at least 4 systems. He trained under William Chow, was a trusted associate of Adriano Emperado, and taught his grandfather's system of Tai Chi at his Wu Shing Academy. He told me that my knowledge was like a PhD in martial arts, but to a novice, little of that matters. It is the basics that they need, and it takes years to pour so much information into those just starting their journey.
Back when I was a freshman at Cal Berkeley in 1973, it was explained why that university had more winners of the Nobel Prize and other high honors than almost any other school on the planet. It was because professors there had teach classes for underclassmen, unlike other institutions where tenured professors could reside in their ivory towers amongst their peers and learned journals. What this meant was they had to constantly ground themselves in the fundamentals of their discipline. It's a lesson that applies to many areas of life.
Aikido, an art in which I spent some time back in the 70's and 80's, has one of the most logical ranking systems I've seen. First and second dan black belts assist more senior instructors. By third dan their skills are more clearly evident, but it generally takes a fourth dan to teach at one's own school. Fifth and higher were quite rare, generally encountered in seminars or as visiting teachers, a practice I truly appreciated in that style. It was a rare privilege if you trained at a school where such presided, but again, much of the hands-on monitoring and correction came from those under the head instructor.
Back around 1990 I met an elderly Taekwondo teacher who held a fifth dan in that art. He flatly stated that ranks beyond that were for politics, not skill. In truth, by the time most get to such a level, their physical skills are diminishing with age. Their value is what they can pass on to those below them. In my own chosen art of Escrima, my teacher, the late grandmaster Angel Cabales often said that his Master's certificate was "for politics. While rank such as that is generally reserved for the closest and most dedicated students, the truth is much of the art will be passed on by the much larger pool of instructors and even advanced but uncertified students. some of whom might be as skilled in the art despite lacking a piece of paper.
This is not to denigrate those who rose to high rank, but simply to point out the pyramid structure of hierarchy. Much like an iceberg, what is seen is only the tip, supported by the vast mass often undetected beneath the surface. In truth, what rises to the top once was below; do not presume those who toil without recognition are less worthy than those who once were such themselves.