He lost it. but if he didn't then. Madara's PS would rape sasuke's PS big time.
Maybe Juubi Jins can't use sharingan techniques for some reason? Or maybe it's
because being an incomplete jin of the juubi causes an inability to use the sharingan.
Sasuke acquired yin style. idk if that enhances susanoo or anything but madara would have his PS powered by juubi chakra... i don't even want to imagine its durability and destructive potential.... It's good thing, kishi nerfed him.How so? In my opinion Sasuke's would be even stronger that Madara's with the Sage powerup.
Maybe it's because he only has one EYE...
I'm guessing it's the same reason Obito couldn't use Kamui while in Juubi form.