Board Thread:Theories and Speculation/@comment-1930928-20191128005957/@comment-34640038-20191128051502

In my opinion, it's not just a every day regular genjutsu. NOBODY was escaping the infinite Tsukuyomi that didn't have either 6 Paths chakra, was a reanimation or those two that happened to be shielded from it by something imbued with 6th paths chakra.

To answer your question to some degree they do have a defense against genjutsu for the exact reasons you stated. They could use their byakugan to see if someone/themselves have been placed under one and act accordingly I would imagine, we just never saw it in manga/anime.

We also see that some Genjutsu just can't be 'Kai'd ' out of. Kabuto tried it when he was caught in Izanagi, and it didn't work there either.