Maybe in that fanfic, Harry has had some really bad experiences with magic that made him hate it. For example, he could have seen magic being misused to harm innocent people. Or perhaps he's tired of the chaos and danger that magic always seems to bring into his life in the fanfic.
Well, it could be that he has seen some really bad magic fanfic. Some fanfic might be full of inaccuracies about magic, and as someone who has a deep connection to magic, it annoys him. For example, if a fanfic misrepresents a spell or a magical creature that he is familiar with, it would make him dislike it.
Well, Harry Potter has been through so much in his own story. Fanfiction could be seen as a misrepresentation of his life and the world of magic he's a part of. It might rewrite his relationships or the significance of certain events, and he doesn't like that kind of false portrayal.
Maybe he hates it because it often distorts the real story or characters he knows. Fanfics can take the story in wild directions that don't align with his own experiences.
In some fanfics, Harry might be made to hate Gryffindor perhaps because the author wants to explore an alternative personality for him. Maybe they want to show how the Gryffindor house's values, like bravado or recklessness, could be seen in a negative light from Harry's perspective.
Maybe in that fanfic, Lupin did something that Harry considered a betrayal. For example, he might have made a decision that put Harry or his friends in danger without consulting them first.
Maybe he has his own idea of what the real magic world should be like. Fanfiction often twists and changes the original story in ways he doesn't like.
Perhaps Harry has his own vision of Gryffindor and the fanfics he's seen don't align with it. He might have a deep - seated understanding of what Gryffindor means to him, like courage, loyalty, and friendship in a very personal way. The fanfics, on the other hand, might focus on more superficial or inappropriate aspects of Gryffindor for his taste, such as focusing too much on power plays or false bravado rather than the true essence of what makes Gryffindor great.
In some fanfics, Harry might hate Dumbledore because he feels Dumbledore has been using him all along as a tool to defeat Voldemort. Dumbledore has been making decisions for Harry without fully considering Harry's feelings and desires. For example, he didn't tell Harry about the prophecy until it was almost too late, and Harry might see this as a form of manipulation.
It could be that in the fanfic's plot, McGonagall has some past connection to Harry's enemies. So, her hatred towards Harry is a result of her loyalty to those she has a history with. This would create a lot of drama and conflict within the fanfic's story.
Well, it could be that the fanfiction writer is trying to subvert the traditional narrative. Harry has always been the hero of Gryffindor, but in this new take, he hates it. Maybe he sees the flaws in Gryffindor that are often overlooked in the original story, like the over - emphasis on courage which can sometimes lead to recklessness and he doesn't like being part of a house with such a one - dimensional view of what's important.