Perhaps the author of the fanfiction has decided to end Harry's story in the wizarding world. It could be due to a lack of new ideas, or they want to explore other concepts. It might also signify that Harry has achieved all he can in that world in the fanfiction and there's no more room for development.
It could be that Harry has faced so many challenges in the fanfiction that he's simply burnt out. Just like in real life, if a person endures too much stress or hardship, they might want to step away. In the fanfiction, Harry may have reached his limit of what he can handle in the wizarding world.
In my opinion, 'harry potter is done fanfiction' can be understood in different ways. On one hand, it could indicate that the fanfiction community has explored all the common themes and plotlines related to Harry Potter. For example, we've seen fanfictions about the characters' further adventures after the books ended, their relationships in different scenarios, and what - if stories. On the other hand, it might also mean that from a creative perspective, new fanfictions are not being produced as frequently or with as much enthusiasm as before. This could be due to the fact that the initial hype around the series has died down a bit, or that the most obvious and appealing ideas for fanfictions have already been written.
Maybe he thinks it distorts the real story of the wizarding world he knows. Fanfictions often take creative liberties that might go against his own experiences and the original narrative.
Perhaps it implies that the essence of Harry Potter's story in the canonical works is complete, and there's no need for more fictional fighting scenarios as seen in fanfiction. The official narrative has run its course, and fanfiction's fighting - related ideas are now redundant.
In fanfiction, Harry Potter can change the Wizarding World in many ways. For example, he might introduce new spells or magical concepts that were not in the original series. He could also have different relationships with other characters, which in turn would affect the social dynamics of the Wizarding World.
It could mean that a Naruto fanfiction has been completed. Maybe the author has finished writing the story they had in mind regarding the Naruto universe.
Some might be shocked and feel betrayed. Harry is a hero to many, so his departure could leave them feeling abandoned. Others might understand his need for a break and respect his decision.
Fanfiction often creates new characters, places, and spells. It can explore different corners of the wizarding world that J.K. Rowling didn't fully cover in the original books. For example, it might focus on a small wizarding village in Scotland that was only briefly mentioned. Writers of fanfiction can also expand on the magic system, perhaps creating new types of magic related to nature or emotions. This way, it gives readers a broader view of the magical universe.
The wizarding world would be in chaos. Harry is seen as a hero and the 'Chosen One'. His death would leave a huge void. The Order of the Phoenix would be devastated and might seek revenge on Draco and those associated with him. Hogwarts would also be in turmoil, with students and teachers alike shocked and saddened. There would be a great deal of fear as well, as Voldemort's forces might see this as an opportunity to gain more power.
Well, perhaps in this fanfiction, Naruto has achieved all he can in Konoha. He might have completed his goals, like protecting the village and bringing peace, and now he feels there's nothing more for him there. It could also be that he's tired of the politics or the way things are run in Konoha and has decided he's done with it all.