I’m not sure that the outcome of Harry Potter is fascist in nature. After Voldemort is defeated there’s no mythic national rebirth, no driving nationalism, no cult of personality at the top, and the society doesn’t treat violence as virtue. What it looks like to me is more of a reactionary neoliberal, paternalist world. Hierarchy is enforced and treated as natural, change is looked at with suspicion, institutions are trusted, and the only problems come about when bad individuals are in charge of those institutions. This is essentially the worldview of 19th century imperialist Britain.
To be clear, though, fascism does exploit these weaknesses in liberal/neoliberal thought to bring itself about and does share some of the superficial look, but I think it flattens the term to label Harry Potter and/or JK Rowling as explicitly fascist. I think at best her work is neoliberal slop and that she has some abhorrent views about gender that people who are fascists would agree with.
I certainly agree that Harry Potter has fascist precursors within it, but that’s mostly my point: Neoliberalism itself is a fascist precursor in real life, or at least fascism easily exploits neoliberalism’s weaknesses. So to that end I think the labels do matter. For example, in theory it’s easier to right the ship and turn away from fascism or recognize its warning signs in a neoliberal society than in an actually fascist one. I.e. turning away from the path of fascism and towards a more egalitarian society might have been easier in 1990s America than it is now in a 2025 America. In much the same way no one thinks JK Rowling isn’t a huge bigot, no one could have reasonably claimed that 1990s America didn’t have its problems. Neither really fit the definition of fascism, although both lead to fascism.
I think the distinction is important because it hopefully makes it easier for imperfect, neoliberal places like Western Europe, Canada etc. that are having problems with rising right-wing movements to recognize problems before it becomes too late, rather than pointing out their weaknesses and jumping straight to a fascism label.