The latest manga chapter of Boruto Naruto Next Generations showcased the defeat of Isshiki and the narrow victory of Kawaki, Boruto, Sasuke and Naruto. However, that victory has come with a price and it almost cost Nartuo and Kurama their lives.
Baryon Mode is the Seventh Hokage’s newest power-up and a level of strength that we have never seen Naruto possess. However, in order to access that power, the life-force of both Naruto and Kurama is drained until one of them dies, which results in the both of them also perishing as well.
This isn’t as big of a deal for Kurama, as he will be reborn later on but for Naruto, it could have killed him. Luckily, Naruto instead was able to source the life-force needed for the transformation from Isshiki, which reduced his life instead but that doesn’t mean that Naruto and Kurama weren’t still affected.
Even Sasuke noticed that this level of power will have a big drawback and mentioned it in the final slides in the previous manga chapter when he asked Naruto for more information. It’s likely that though both Kurama and Naruto survived, their overall powers may have been weakened significantly, just as Might Guy’s power has been since accessing the Eighth Inner Gate.
We have also already seen Sasuke’s Rinnegan taken away from him at the end of the last chapter so, I wouldn’t be surprised is Naruto’s power is also reduced to make way for the next generation. The next generation such as Boruto and Sarada cannot truly progress if their parents are always running in to help them.
Considering Kurama most likley took on the bulk of the draining during the time Baryon Mode was activated, as Kurama has a lot more Chakra reserves than Naruto naturally, he may have reverted to his child-like self or even go into a long and deep slumber to recover. Without Kurama, Naruto is still powerful but nowhere near his best and thus, this could be the power-down needed for Boruto to truly need to improve.