Some fans might like it. They could see it as a way to show Naruto's strict parenting side and how he is trying to instill good values in Boruto. It would add a new dimension to their relationship.
Many fans would be divided. On one hand, they understand the need for discipline in the story. On the other hand, they have a certain image of Naruto as a kind and patient person. So, it would really depend on how the fanfiction is written and how well it justifies Naruto's actions.
Some fans would be extremely shocked and angry. Kushina is a beloved character, and Naruto slapping her goes against the loving relationship they should have as mother and son. They might feel that it's a disrespect to the original story's characters and themes.
Hinata might be shocked at first. She has always adored Naruto, and this sudden act of aggression from him would leave her stunned and unable to process it immediately.
They could be shocked. Some might not expect the wild ideas that fans come up with in fanfiction.
Naruto would likely be excited. He loves his son so much that seeing different stories about Boruto would be like seeing different potential futures for him. He might even get some inspiration from the fanfiction to give Boruto some advice in real life.
Boruto's reaction would be complex. He'd be heartbroken, for sure. He might start to question his own worth and purpose. But over time, he'd realize that he has to carry on Naruto's legacy. He'd become more serious and focused. He'd also become more empathetic towards others, understanding the weight of sacrifice. He might even start to study Naruto's techniques and leadership style more closely, trying to emulate the things that made Naruto such a great Hokage and hero.
Some fans would be very disappointed. Naruto is a character that represents hope and friendship in the original series. So seeing him die alone in a fanfiction goes against the positive themes of the original. They might not like this dark take on the character.
There would be a lot of mixed reactions. Some hardcore fans who have dedicated a lot of time to writing Naruto fanfiction might feel betrayed. On the other hand, there are those who are more focused on the official Naruto products like the anime, manga, and games, and might not be as affected. However, overall, it would create a stir in the Naruto fan community and lead to a lot of discussions and debates.
One possible plot could be that Boruto does something really reckless, like using a dangerous jutsu without proper training. Naruto, as his father and the Hokage, slaps him to snap him out of his overconfidence and make him realize the seriousness of his actions.
Hinata would be completely devastated. She has always been deeply in love with Naruto, and his sacrifice would leave her heartbroken. She would still be strong for Boruto, though, and try to support him in any way she could.
The villagers would likely be in shock. Naruto is a beloved figure, but killing his own son would be a very controversial act. Some might turn against Naruto, believing he has gone too far. Others might understand his reasons if they knew the full story, but still struggle with the morality of it.