It could also lead to new alliances. Other villages might see Naruto's stance and try to form alliances with him, seeing an opportunity to weaken Konoha. This would then put Konoha in a more precarious position and force them to reevaluate their relationships with other villages.
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.
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.
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.
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.
Well, it completely flips the idea that Naruto is always loyal to Konoha. In the original story, Naruto's main goal was to protect the village. Here, his refusal makes Konoha vulnerable and forces the other characters to re - evaluate their relationship with Naruto and also their own role in protecting the village.
It could also be that Naruto has grown disillusioned with the politics in Konoha. Constant power struggles, nepotism, or unfair treatment of certain groups within the village might have pushed him away. He might feel that his help would only be enabling a corrupt system.
The story could develop with Konoha facing various threats without Naruto's help. They might initially struggle and have to rely on their remaining ninja forces. This could lead to the development of new characters or the growth of existing ones as they are forced to step up. Meanwhile, Naruto could be off on his own journey, perhaps exploring the true nature of the Rinnegan's power or trying to create a new world order without Konoha's influence.