Well, it could be for a plot device. Writers might want to create a more complex and angsty story. By having Kushina ignore Naruto, they can explore themes of abandonment and self - discovery. It adds a layer of drama to Naruto's character development.
Naruto could ignore fanfiction because it often contains elements that are not part of his reality. The fan - made stories might distort his character or the relationships he has. For example, some fanfiction might pair him with characters in a way that doesn't make sense to him or goes against his values, so he just ignores it.
Perhaps in this fanfiction, Naruto turns to the darker side of the ninja world. Since he lacks the love and guidance from Minato and Kushina, he might be more easily influenced by Orochimaru or other villains. He could start to believe that power is the only way to get respect and recognition, and thus embark on a path that is different from his canon self. He might also form unexpected alliances with characters who are also outcasts in the shinobi society.
One possible reason could be a misunderstanding. Maybe Minato thought Kushina had done something to endanger Naruto when in fact she hadn't. In the heat of the moment, he lost his temper and slapped her.
Naruto's character development in such a fanfiction would likely be very different from the original. He may become more withdrawn at first, hiding his pain of being ignored. But as time goes on, he could develop a stronger sense of self - reliance. Since he doesn't have his parents' support, he has to figure things out on his own. This might make him a more independent and resourceful ninja in the long run.
In NaruHina fanfictions, Naruto might ignore Sasuke because he finally finds true love and stability with Hinata. His focus shifts from the turbulent relationship with Sasuke to building a future with Hinata.
They might find other aspects of the fandom more appealing.
It could be a creative exercise in exploring how a single event, like Kushina killing Naruto, would change the entire Naruto universe. Writers might be interested in seeing how other characters would react, how the story would progress without Naruto, and how the themes of the original story would be altered. For instance, the theme of friendship and mentorship would be severely affected. It's also possible that the writer wants to shock the readers and make them think about the characters in a completely new light.
Well, in some fanfictions, the idea of Naruto hating Kushina might be a very dark and twisted take. Maybe the author wants to explore extreme emotional scenarios. As for Naruto loving in this context, it could be about different kinds of love - like platonic love for his friends or a romantic love for a character. Fanfiction often takes liberties with the original story's relationships.
It might be because of a misunderstanding. In some fanfics, a false rumor could spread about Harry. Ron and Hermione, believing it to be true, might decide to distance themselves from him. Say, there's a rumor that Harry is involved with dark magic in some way, and they, being the 'good guys', think they need to stay away.
In Naruto, the story is built on themes of family, love, and sacrifice. Minato and Kushina are important figures in Naruto's family tree. Minato was a great Hokage and Kushina was a strong - willed woman. Their love for Naruto is a fundamental part of the story's emotional core. So in fanfiction, it's hard to imagine a deviation from this where they would abuse Naruto. Most fanfiction writers prefer to stay true to the spirit of the original story, which is full of positive family values.