Why is the reflection of the genjutsu of IT not the "rinnegan" reflection instead of a regular one like sasuke's genjutsu? Sasuke eye is similar to the Juubi's, but not the same, close enough. But the IT people reflection was a regular rinnegan. By your logic the genjutsu would of canceled itself...I don't recall this being stated. Only that "a Rinnegan can cancel genjutsu from another Rinnegan", meaning any Rinnegan could.
Unless otherwise stated, there's nothing special about Sasuke's Rinnegan except it's appearance.
Also if any rinnegan can cancel any genjutsu then why is one rinnegan is required to create it? That's like saying just because a random uchiha has 3 tomoe he can cancel Itachi's genjutsu.
How is sasuke ability is special if Kaguya also has it :3? Its only a similarity thing, but still different. The only eye we know is the same as sasuke's is the yin yang one Obito was talking about with Konan.Every rinnegan has the six paths technoqe, every rinngan has genjutsu but not every user can use it and S/T is sasuke's special rinngan ability just like madara's limbo