It could also be because of Naruto's own insecurities. He might be afraid that Hinata's actions are drawing too much unwanted attention or putting herself in harm's way, and he yells to try and protect her in his own, brash way. He doesn't want to lose her, but doesn't know how to express it other than through yelling.
Perhaps there is some external pressure on Naruto, like from the village elders or other powerful ninjas. They might be pressuring Naruto to keep Hinata in line, and he yells at her as a result. He doesn't really want to, but feels he has no choice in order to satisfy those in power.
Hinata might be very hurt. She's a sensitive person, so Naruto yelling at her could make her feel small and sad. She might start to doubt herself and her abilities.
One possible reason could be that Harry did something reckless without consulting Hermione. For example, if he went off on his own to face a dark wizard, Hermione, being the cautious and logical one, would be furious. She values planning and teamwork, and Harry's solo actions might seem to her as endangering himself and others needlessly.
One possible reason could be Snape's unfair treatment of Gryffindor students. Hermione, being a strong advocate for justice, might not tolerate his constant bias against her house. She could yell at him when he unjustly deducts points from Gryffindor for minor reasons.
One possible reason could be Sakura's constant pining for Sasuke. Naruto might feel frustrated that she's so focused on Sasuke when he's right there for her. In the Naruto universe, Naruto has always been a bit jealous of Sakura's love for Sasuke, and in fanfiction, this could be amplified to the point where he yells at her out of pent - up emotions.
One possible reason could be that in the fanfic, Hinata has different personal goals or ambitions that she feels would be compromised if she were to be with Naruto. For example, she might be more focused on her family duties or her own ninja training and career, and she believes that a relationship with Naruto would distract her from those things.
It could also be due to jealousy. If Naruto is spending a lot of time with other female characters, Hinata might get angry. Even though she is usually shy and reserved, her love for Naruto could turn into anger if she feels threatened by his closeness to others.
Another reason could be that Hinata herself undergoes a significant transformation. Maybe she has a spiritual awakening or a change in her life goals that make her realize that her love for Naruto was more of an infatuation based on her younger self's ideals, and as she grows, she no longer feels the same way.
One reason could be to seek a new life away from the political drama in Konoha. Naruto has always been in the spotlight and has faced many political challenges. Hinata, being by his side, might support his decision to leave for a quieter place. Maybe they want to raise their family in a more peaceful environment, away from the constant threat of enemies targeting Konoha.
One reason could be misunderstanding. Maybe Hinata sees Sakura getting too close to Naruto and misinterprets their friendship as something more. And Sakura, on the other hand, might not be fully aware of Hinata's feelings for Naruto and act in a way that Hinata perceives as a threat.
One possible reason could be a huge misunderstanding. Maybe he thought Hinata did something really bad to his friends, like unknowingly leading the enemy to them. Without knowing the truth, his hot - headed nature made him lash out.