Sasuke was just being a Decoy, he wasn't using his Full Power

[The Sage Of Six T9]

Diversion and decoy are the same ! He played possum so that naruto could attack

 

[Kronnic]

If Sasuke is being a decoy is because he is playing the same role as Hamura while Naruto is playing the role of Hago...
But, Kaguya was not distracted at all.. Naruto is on a different level from Sasuke..