Naruto's own reserves never replenished, in fact kurama stated their chakra was near exhausted due to the war.Also got this chakra restored twice. Got yin kurama who logically should have more chakra than yang since he wasn't fighting much. And tailed beasts chakra added with Hagoromo's. :sdo3: Yea he sure was out of chakra.
OT Sasuke and Naruto fought had more destruction than any Hashirama vs Madara fight did and that was with both of them literally exhausted from the war arc.
