When I think of a die hard Harry Potter fan, what I think is a normie. a vapid tasteless normie who doesn't know anything about the greater science fiction or fantasy genre who's immature desire for wish fulfillment and simplistic characters keeps them from seeking out greater authors. If they ever attempted the works by Ursula K. Le Guin or Terry Pratchett they would have either put aside Rowling, or more likely, quickly loose interest and revert back to simple pleasures.
Of course, this is a completely unrealistic perspective. It is unnecessarily elitist and patronizing. Nonetheless, it's still persistent. So I'd be really interested to hear the perspective of super fans of the series like that actually have a wide-ranging experience with different fantasy genres as a comparison point, what they think of those authors people often hold up as superior to Rowling, and why they find Harry Potter so special.

in over a year either.

