In this fanfiction, his hiding of his true self can be seen as a part of his struggle. As he goes through various challenges, he has to decide when and how to reveal his true self. This decision - making process is crucial for his character growth. For instance, if he hides his true self from his friends, it can create tension in those relationships, but when he finally reveals, it can lead to a deeper bond. This back - and - forth struggle helps in shaping his character over time.
One possible reason could be fear of rejection. In the Naruto universe, he has so many expectations on him. If he reveals his true self which might be more vulnerable or different from the image people have of him, he could be shunned. For example, his experiences as a Jinchuriki made him an outcast initially, so he may be afraid to show more of his true self in case it causes more isolation.
Perhaps he has hidden the full extent of his Sage Mode abilities. He might be able to stay in Sage Mode for a much longer time than he has shown so far, or have some other undisclosed powers within that mode, like the ability to sense enemies from much greater distances.
Sasuke could be one of the people who help him. Despite their past differences, they have a deep bond. Sasuke has his own skills and knowledge that could be useful in Naruto's situation, like his Sharingan abilities which could help in detecting enemies while Naruto is hiding his face.
He might use some special jutsu or seals. For example, he could use a sealing technique to suppress the signs of his bloodline. This way, others wouldn't be able to detect it through normal means like sensing chakra.
It could also be part of a strategic move. By hiding his bloodline, he can surprise his opponents in battle. They would underestimate him based on not knowing about his true powers, and then he could turn the tables on them when the time is right. This gives him an edge in combat situations.
One possible reason could be that his eyes hold a special power that he doesn't want others to discover easily. For example, it might be a new type of Sharingan or a unique ability related to his Uzumaki heritage that he needs to keep secret to protect himself or those around him.
Maybe he wants to surprise his opponents in battles. He could be waiting for the perfect moment to reveal his full power and turn the tables on his enemies.
One possible reason could be that he doesn't want others to pity him. Naruto has always been a proud and strong - willed character. His scars might be a reminder of painful past experiences, and he prefers to deal with them privately rather than showing vulnerability to others.
He might want to protect himself. If others know how smart he is, he could become a target. Enemies might see him as a greater threat and go after him more aggressively.