It could be that Naruto is possessed by an evil spirit. This spirit wants to destroy the Leaf Village for its own reasons. Naruto, under its control, would first cut off the village's supply lines, making it difficult for the villagers to get food and resources. Then, he'd start attacking the ninja in the village one by one. He might even use his Nine - Tails chakra in a very destructive way, not caring about the harm it would cause to the place he once called home.
In a 'naruto destroys konoha fanfic', one possible plot could be that Naruto is pushed to the edge by the villagers' constant mistreatment and the hidden secrets of Konoha's leadership. He discovers some dark deeds that the village elders have been involved in, like using him as a pawn without his knowledge. This betrayal could fuel his anger and lead him to decide to take revenge on Konoha.
Well, it could start with Naruto seeing the dark side of bloodline powers being misused. So he decides to take matters into his own hands and develop a method to destroy bloodlines. This could lead to a huge rift in the ninja community, with some supporting him for trying to create equality and others opposing him because they value their unique family abilities.
Choji would be sad and also a bit scared. He has always been a loyal friend to Naruto. He might not be as aggressive in trying to stop Naruto as some of the others, but he would try to reason with him, talking about their friendship and how the village has also been a home to Naruto. And Ino would use her mind - related jutsu to try to break any possible mental influence on Naruto if there is one, while also trying to reach out to him emotionally.
A possible plot might involve Naruto being exposed to some ancient and powerful knowledge or artifact. This discovery gives him the means to 'destroy' bloodlines in the sense that he can change the very nature of chakra within a person. He might use this new - found ability to break the cycle of bloodline - based power hierarchies. He could start with the major clans like the Uchiha and Hyuga, and as he spreads his influence, the concept of bloodline superiority slowly crumbles, leading to a new era in the Naruto world where a person's worth is determined by their own efforts and skills rather than their bloodline.
One possibility could be that Naruto is somehow transported to the world of Greek mythology where Olympus exists. Maybe his powerful jutsu are seen as a threat to the gods on Olympus. He could start by accidentally causing chaos in a nearby village which gets the attention of the minor gods. As they try to stop him, he realizes he has to fight back to protect himself and in the process, his attacks end up targeting Olympus.
Maybe Naruto gets some sort of dark power that makes him go berserk and start destroying everything in his path. For example, he could be influenced by an ancient evil curse.
One common theme could be redemption. Even though Naruto is 'destroying' Sasuke, it could be seen as a way to save him from a path of self - destruction. Another theme might be power struggle. The idea that Sasuke's pursuit of power has led him astray and Naruto, with his own power, has to put an end to it. Also, friendship could be a theme. Naruto might be doing this out of a sense of love for his friend, that he can't let Sasuke continue down this dark path.
I'm not sure specifically as there could be many different interpretations in fanfics. It might involve Harry getting fed up with the magical press for misreporting or invading his privacy and taking some sort of drastic action to put an end to their antics.
One common plot point could be Naruto's sudden change in ideology. He might shift from being a protector to a destroyer due to some extreme event. Another is the reaction of his friends and former allies. They would be shocked and try to stop him, which could lead to some intense battles. And often, there would be a mysterious force or character behind his transformation.
In this kind of fanfiction, Naruto might be banished due to some false accusations or political conspiracies in Konoha. Once banished, he could decide to destroy Konoha out of anger and a sense of betrayal. He may have learned powerful jutsus during his exile and use them against the village that once rejected him.