I think this puts consciousness on too high of a mystic pedestal. It may be impossible for an individual to experience reality outside of their own consciousness, but that does not preclude studying how it works. What makes you think that it is impossible to observe someone else’s consciousness? and more importantly, what evidence do you have to substantiate that claim?
After all, we research many aspects of reality obliquely. Our understanding of subatomic particles comes mostly from smashing larger particles into each other and seeing what pops out - not by observing subatomic interactions directly. We can do effective research by inference.
Personally I don’t believe that there is anything in our existence that is beyond our understanding, given enough time and study.