This is a day Naruto fans would never have thought would come, however, it's here; the day Naruto has taken a step backward. Throughout Naruto's journey, he has constantly improved to the point of being the greatest ninja to ever live, although, his powers now seem to be diminishing.
In episode 21 of Boruto Next Generations, fans are watching as Naruto Gaiden being animated, with the story of a new villain in Uchiha Shin threatening the world by bringing back the Akatsuki. As a result, Naruto and Sasuke hunt him down and begin to fight against the Sharingan user, however, this is not the same duo that fought against Kaguya all those years ago. It seems that Naruto has lost his touch since becoming Hokage, with Kurama confirming it.
In episode 21 Kurama said that Naruto had lost all battle sense hinting that he has become quite rusty, as he was struck by Sasuke's sword. Naruto looks as if he has lost the drive he once had and has become weaker as a result. Yes, Naruto still wields the power of Kurama, the other Tailed Beasts, Sage Mode, Six Path Sage Mode and his other powerful Ninjutsu techniques, however, he looks less battle ready.
Kurama even hinted that it has been quite a while since Naruto went all out in the previous episode. Meanwhile, in addition to being rusty, Naruto looks unfit. Yes, he still has incredible chakra reserves, however, he lacks overall fitness. This is evident, as all of Naruto's fights to date in Boruto have seen the 7th Hokage barely move. All Naruto now does is use Kurma's arms, which could be to cater for the fact that he has lost a great deal of fitness. However, in his defense, it looks as if Naruto's healing abilities have improved quite a bit, as he healed himself almost instantly after removing Sasuke's sword embedded within his stomach.
Naruto is still the greatest ninja to ever live at his peak, however, it seems as if he is beyond his peak at this stage in Boruto, which is sad, as he isn't that old. This could be how Kawaki defeats Naruto in the future as if this trend continues, Naruto's skills will only diminish further.