The article and source data says that some only get 7 dimensions of connectivity. But what that means, is not known or written of. So the meaning is ambiguous. perhaps it is connected to higher brain function in complexity of data analysis and speed of analysis. Which means an expanded data and knowledge base, for starters. But that is all conjecture at this point, so who really knows. But the data for the structures did indeed arise and be found real, in the study. The indicators are in the mentioned directions.
So it may play out in hearing function and realization as tied to intellect.
Ears have an IQ just like conscious and unconscious cognition does, and we each possess our genetic and learned variances in those areas.
So some can't hear it and can't intellectually wrap their head around it. But that does not necessarily mean it is permanent, it may simply be all about levels of exposure to clear and clean enough audio systems that may allow them to systematically find and discover.
Some project emotion and refuse, as a way of living life in a world of dogmatic negative proofing. These are the most difficult and repetitious... and grind forums of decent audio people...into the ground. If they be allowed to continue, that is the result.