One possible reason could be a major betrayal. Maybe someone he trusted deeply, like a close friend or a mentor, turned against him. This would make him lose faith in people and become cold as a form of self - protection.
It could also be due to the loss of too many people he cared about. If he witnessed the deaths of his friends one after another in battles, he might become distant as a way to avoid the pain of future losses. He would start to keep people at a distance so that he wouldn't get hurt again.
One possible reason could be a major betrayal he experienced. Maybe someone he trusted deeply, like a close friend or a mentor, turned against him. This would make him more guarded and distant to avoid getting hurt again.
One possible reason could be a great betrayal. Maybe he discovers that someone he deeply trusted, like a close friend or a respected mentor, has been using him all along. This would shatter his trust and make him withdraw from people, thus becoming cold.
One reason could be to explore a different side of Naruto's character. In the original series, he's so warm - hearted, but by making him cold and distant, the writer can show how different events could have shaped him in an alternate way. Maybe he faced more hardships or betrayals that led to this change.
One possible reason could be that he has faced a lot of misunderstandings within the family. Maybe his family has certain expectations that he can't meet, and over time, this has led to his coldness. For example, if his family doesn't understand his dreams or ambitions, Naruto might feel alienated.
One possible reason could be a feeling of betrayal. Maybe he found out some long - hidden family secrets that made him lose trust in his family. For example, if he discovered that his parents had made a deal with some dark force in the past that had negative consequences for him or the village.
One reason could be a great loss. Maybe he lost someone really important like Jiraiya in a more tragic way that made him shut down. Another could be that he discovered some dark secret about the village that made him lose faith in everyone.
It could be due to a new jutsu he's trying to master that has some side effects on his emotions. Maybe it's a powerful ice - based jutsu that's making him cold in nature as well.
Perhaps he has trust issues. He might have been betrayed in the past, so now he keeps everyone at a distance to avoid getting hurt again.
Another reason could be the influence of a powerful and dark entity. If Naruto is somehow possessed or influenced by a dark chakra or a malevolent spirit, it might change his personality completely. He could start to push away people who care about him because the entity wants him to isolate himself and be more vulnerable to its control.
It could be due to a personal loss that has hit him really hard. Maybe he lost someone very close to him, like Jiraiya all over again, but this time it has broken him in a way that he shuts everyone out. He might also be under the influence of a new power that he doesn't fully understand yet, and this power is affecting his emotions, making him cold as a side - effect until he learns to control it.