They were equal because Naruto used most of his power against Kaguya and Naruto wasn't using the other Bijuu's abilites. Yang BM is stronger than EMS and BSM is even more as Sasuke's jealousy shows and the fact that Naruto was at less than half or at half his BM chakra reserve whenever Naruto went BSM which Sasuke was being shown to be even to, so full power Naruto would be stronger their.
Now let's add in their other powerups: Sasuke got Hashirama's cells from Kabuto which increases stamina, chakra, increase healing (as that's why it was being used), and power up Jutsus (like with KA), got some chakra from Hashirama, got Rinnegan from the Sage. Naruto lost Yang Kurama but gain Yin Kurama, gain access to Rikudo senjutsu, and gain access to the other 8 Bijuu's abilities.
Now if you took both fighters and made them full power, Naruto would win since Sasuke did use a lot of chakra but said chakra does not equal to the amount Naruto used. Also Naruto would have access to all of the abilities he had prior to the fight with Sasuke that he didn't use and would have all of his truth seeking balls. Both are still new to their power but DB said Naruto gain knowledg of chakra with his RM so you can say Naruto could learn to use his power in battle which he already was doing against Madara and Kaguya as Sasuke would with his Rinnegan.