Arguing on behalf of some hypothetical individual who may or may not ever exist is a path fraught with peril. That's how people justify all kinds of crazypants positions. "I'm not arguing for myself. This isn't about me. It's about some other person who may come someday and be the savior of us all." I would say, if that guy does come, he will probably start his own style, and make himself the grand poobah. And if he doesn't, he's making a choice to stay. I think the saying goes, "Don't let the door hit ya where the good lord split ya." The guys you reference chose to stay and remain in the organization. They didn't have to. If they were truly as exceptional as the founder of the art, they could have done so.
I get it. Conceptually, in America now, we want parity. The idea that there are some things that are unattainable is distasteful to us. We tend to lump everything together and say, "How come that person over there can't do that thing over here?" We like to promote the idea that, if you work hard enough, you can do anything, and nothing is off the table. So, the idea that if you train in a style for decades, you can never achieve level 60 just doesn't feel right. However, discrimination is freedom. We have a relative few protected bases that are exceptions to the rule. I'm pretty sure that the Gracies are not straying into any protected base here. In general, in America, we allege to respect the rights of people to discriminate in whatever ways they choose. provided they do not violate the law. We discriminate in many ways and for many arbitrary reasons all the time. Discrimination is a fundamental tenet of freedom, and without the ability to discriminate, we cannot be free.