In some fanfictions, it could be because of a misunderstanding. Naruto's powers might be misinterpreted as something evil or dangerous. For example, if he has a new power that looks menacing but is actually harmless, the villagers might panic and demand his banishment without really understanding the truth.
One possible reason could be fear. Naruto's 'godlike' powers might be too much for the village to handle. They could be afraid that he might accidentally cause destruction. Another reason might be envy among some of the villagers or ninja. They may not like that Naruto has become so powerful all of a sudden and want him out of the way.
One possible reason could be false accusations of a serious crime. For example, if he was wrongly blamed for a major attack on the village. Another reason might be political intrigue. Some powerful figures in the village might see Naruto as a threat to their power and find a way to banish him to maintain their control.
One possible reason could be feeling betrayed by the village leaders. Maybe they made decisions that Naruto strongly disagreed with, like how they treated certain groups or individuals. If Naruto felt that Konoha was no longer the place that stood for justice and fairness as he once believed, he might abandon it.
The banishment can also affect the relationships of other characters. For example, Sasuke might have a different reaction. He could be more sympathetic to Naruto's situation or he could see it as an opportunity to become the top ninja in Konoha without Naruto's competition. Also, characters like Sakura might try to find a way to bring Naruto back.
Perhaps Naruto discovers some dark secrets about Konoha that go against his values. Like if the village has been involved in unethical practices that he can't overlook. This could be things like using underhanded tactics against other villages, which would make Naruto, with his strong sense of justice, turn against Konoha.
One possible reason could be that she is wrongly accused of a serious crime she didn't commit. For example, if there was a major theft in the village and false evidence was planted against her. Another reason might be that she has some new and powerful abilities that the village elders fear. They may think she could become a threat in the future, so they banish her to protect what they see as the village's stability.
Another reason might be that Naruto is seeking a greater purpose. In the fanfiction, his 'godlike' state could make him realize that there are threats out there that he can't face while being tied to Konoha. He may leave to protect the world on a larger scale, believing that he can be more effective away from the village.
Perhaps he discovered some dark secrets about Konoha that made him lose faith in the village. For example, if he found out that the village leaders were involved in unethical or immoral activities that were against his values, it could make him hate Konoha. He might also feel betrayed if his so - called friends turned their backs on him for some reason.
Perhaps Naruto has found a new purpose or community outside of Konoha that values him more. He may be so content with his new life that he simply doesn't want to get involved with Konoha's problems anymore. Konoha's actions towards him could have made him realize that his loyalty was misplaced all along.
One possible reason could be that the villagers never fully accepted him despite his efforts to protect Konoha. They might have continued to treat him as an outcast, which could have led to his growing resentment and ultimately his banishment if the situation got out of hand. For example, if he was wrongly accused of a serious crime and instead of getting a fair trial, the village elders decided to banish him.
Another reason might be a lack of acceptance. Despite all his efforts, if Naruto still feels like an outcast in Konoha, he could decide to defect. He might think that he can find a place where he is truly understood and valued elsewhere.