One reason could be that other characters might be more popular among fanfiction writers. For example, if there are more glamorous or complex characters in the same universe, they might overshadow Percy. Another reason could be that the storylines involving Percy are not as easy to explore in fanfiction. Maybe his character arc in the original work is so straightforward that it doesn't offer much room for creative reinterpretation.
Well, sometimes it's about the fan base's focus. If the majority of the fan base is more interested in a certain aspect like romance between other characters, and Percy doesn't fit into that narrative easily, he could be neglected. Also, lack of inspiration among writers. If they don't have a fresh take on Percy's character, they might choose to write about others. In addition, the popularity of certain ships (character pairings) that don't involve Percy can also lead to his neglect in fanfiction.
Perhaps there are family secrets or misunderstandings. His family might have some hidden agenda or past issues related to Naruto's brother that make them focus more on him. It could also be that Naruto's brother is seen as more compliant with the family's traditions and expectations, while Naruto is more of a free - spirit, which causes the neglect.
Perhaps there has been a misunderstanding. Maybe Harry did something that was misinterpreted by his mates, leading to their neglect.
Well, perhaps it's because the Naruto universe has such a distinct and complex world - building. When it comes to crossovers, it's difficult to blend it seamlessly with other universes. For example, if you cross it with a modern - day superhero universe, the differences in power systems, cultures, and values are huge. This might make the crossover fanfiction seem forced or not as appealing, leading to it being neglected.
It could be because Percy is different. If he comes from a different background or has a unique personality trait, the bullies might target him. In the fanfiction, if Percy is from a different race or has an unusual way of speaking, the bullies might pick on him for not being like them.
Perhaps a prophecy misinterpretation. If a prophecy was misread and it seemed like Percy was the cause of great evil to come, the gods might take drastic action. For instance, if the prophecy spoke of a 'child of the sea' causing destruction, and they wrongly assumed it was Percy without fully understanding the context.
It could be that his sister has some special abilities or talents that the family or the village values more. For example, if she has a very rare and powerful bloodline limit, everyone's attention would be drawn to her. In a ninja world, power and potential are highly regarded, so Naruto might be overlooked because his sister seems to have more of that 'special something' at first glance.
In fanfiction, Percy being rich might be a way for the writer to explore different aspects of the Percy Jackson universe. Maybe they want to show how the world of demigods would interact with wealth. It could also be a way to make Percy more like a modern hero, who often has access to a lot of resources. Plus, it can lead to comical situations where Percy, who is used to a more simple life, has to deal with the trappings of being rich, like dealing with butlers or managing a large estate.
It could be that Percy has a special connection to one of the major gods. For example, if he's related in some way to Zeus or Poseidon, the other gods would be extra careful with him. Also, Percy might have done something in the past that made the gods feel indebted to him, and this overprotectiveness is their way of repaying him.
Love could be the main reason. Since he loves Annabeth deeply, he doesn't want to lose her, so he becomes possessive.
One reason could be for a fresh take on the story. Writers might want to break away from the typical demigod narrative and explore a darker, more supernatural side of the Percy Jackson universe. Another reason could be to create a more complex and morally ambiguous character. By making him a demon, they can introduce new conflicts and relationships.