You also have to take into consideration the fact that Naruto has being fighting a lot longer than Sasuke and wasn't at full power while Sasuke was in a better condition than him. Naruto was in intense training (with no rest mind you) before even going into the war where he used up a lot of chakra and was even injuried
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(used a ton of chakra which makes you exhausted) and
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(He got injured and told be no to taking a break). Then he split his power 1/13th when he made 12 clones
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and we know Naruto feels a percentage of what his clones feel and since they were all fighting he would feel exhausted even more which he shows right before going BM for the first time
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Naruto got healed by Sakura 2x after that and we know Tsunade make people rest for days to weeks even after they're healed because their bodies don't fully recover. We see this in part 1 with Naruto after his fight with Sasuke (VoTE), with Kakashi after using Kamui for the first time in Shippuden and Sasuke after he was healed from the wounds Itachi gave him when he followed Naruto to find Itachi.
Not only that but BSM wasn't even at full power, Kurama was in the process of trying to gather more chakra and when Naruto tried to go BM his KM went out completely
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. Then Yang Kurama got some chakra from Yin Kurama
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and after that Naruto and Minato gave a ton of chakra to the Shinobi alliance and Minato had to have used a lot of chakra to FTG them all away
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So Then Naruto and Minato went BSM/BM and used a Super Senjutsu Rasengan and Senjutsu tbb before having their chakra absorbed. Yin Kurama then gave the chakra he had left to Yang Kurama
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. Naruto uses his charka to increase the defensive capabilities as he did in page 4-8:
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. Then he tanks this
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for not only himself but over 20k ninjas (they had like 50k before whicle there were 80k Zetsus I believe)
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and
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. You can see it knocked him out of KM doing so.
So taking all of that into consideration, Naruto at full power and strength could just increase his defensive power using more chakra as he did for thousands of others and wouldn't be as wiped out as he is.