Why you tried to sugarcoat it? You said it as if bee didn't use bijuu against Sasuke.
Probably because Bee fought Taka and not just Sasuke. When Base Bee fought Sasuke he took him down which would end the fight had it been 1 on 1. Suigetsu and Juugo jumped in to help Sasuke before that as well. This was also Bee not being serious. Naruto from Pein arc would put up a better fight but would lose to Bee.
Naruto would have won becuz even if he wasn't a perfect jin at the time like Bee , Kurama has way more power than Gyuki aka 8tailz.
Kurama was able to breakout of CT and match 5+bijuu's bijuudama. Bee/8tailz said it themselves ''wow the 9tailz is insanely powerful.''
I don't think even Bee could of taken the kyuubi down.
Jinchuurikis are stronger than wild Bijuus because they can better focus the Bijuu power. Bee would beat even a rampaging Kurama who would be around version 2 4 tails-6 tails. It was Naruto as a prefect Jinchuurikis that fought 5 Bijuus and Nagato was trying to capture Naruto not kill him plus said he he could of made it bigger if he chose to.
Bee negs Naruto with his BM. Without using bijuu Naruto negs.
A base Bee who was not serious pretty much neg Sasuke and you think Naruto would win? Bee doesn't need BM to win, probably Version 1 4-6 tail mode.
Naruto would have won just like how he beat the crap out of kyuubi,just several giant rasengans and one giant rasenshuriken would do. Anyway if he is eventually getting beat he can always end up in rage and use kurama rampage mode
Jinchuurikis are stronger than wild Bijuus, the 8 tails stated this and even Hashirama showed to be more worried after the Juubi had a Jinchuurikis than he was before it did. Bee in version 1 3 tails mode was too fast for Sasuke's 3T to see and he needed to have Karin keep track of Bee so Bee can dodge attacks better than Kurama who is a bigger target. Bee in BM would just outsmart a wild Kurama if that was the case.