Maybe he has some personal grudges or misunderstandings within the family in the fanfiction. It could be that something happened in the past that made him feel betrayed or unappreciated, so he refuses to offer help.
The plot may start to revolve around the family's struggle without Naruto's help. This could involve them trying to prove that they can manage without him or trying to find a way to make Naruto change his mind. At the same time, Naruto's own journey might continue separately, but his actions or lack thereof will always be in the background of the family's situation. It could also lead to new alliances or enemies being formed as a result of the family's new situation without Naruto's support.
Maybe he has some personal grudges against the village. For example, he might have felt betrayed by the village in the past and that made him reluctant to offer help.
One possible reason could be past betrayals. Maybe he was mistreated by the village in some way, like being blamed for things he didn't do or not getting the support he needed when he was younger. So he feels no obligation to help.
The village would likely be in a state of panic. Since Naruto is very powerful, without his help, they might be vulnerable to attacks. They would have to find other ways to defend themselves, which could be difficult.
Maybe in the fanfiction, Naruto has discovered a new family or group of friends outside the village who are in need of his help more urgently. He has to prioritize them over the village that banished him. He could also be trying to teach the village a lesson about the consequences of their actions by refusing to help.
Perhaps Naruto with the Rinnegan has seen a darker side of Konoha that he was previously unaware of. It could be something related to the village's past secrets, such as hidden experiments or unjust actions towards other ninja clans. This new knowledge makes him so disillusioned that he refuses to offer his help. Also, he might have formed new alliances outside of Konoha that he values more and that conflict with Konoha's interests.
Perhaps Naruto has been pushed too far by the villagers' continuous mistreatment. Even though he has saved them multiple times, they still show hostility or indifference towards him. So, in the fanfiction, he decides not to help Konoha anymore as a form of self - protection and to break free from this one - sided relationship.
The story could progress with Konoha facing a great threat without Naruto's help. The village might initially struggle to find a replacement for Naruto's power. This could lead to a sense of panic among the villagers and the leadership. Some might start to regret their past actions towards Naruto.