This begs the question, does the G-factor (IQ) curve have diminishing returns and are humans meaningfully on the diminishing returns side of the curve?
It's not at all obvious that a super AI would have an intellect incomprehensible to a human the same way a human is to a chimpanzee.
Or another way to phrase it, it's not at all obvious that an AI can exist that would be incomprehensible to a very smart human, it may however reason much faster than such a human.