Matter of perspective; one in the 100~150 billion sapiens (or more) that have gone before and the rates go up. It's also possible rates are underestimated, as we have only tested a relatively small sample compared to N=all
If we test every living human, we can figure out who is the very smartest one. That person has a 1-in-<current_pop> intelligence, from which we can calculate their IQ. That IQ is nowhere near 200.
It would be handy to have standardized test answers from every human ever, but sadly most are dead as you point out.
It would be handy to have standardized test answers from every human ever, but sadly most are dead as you point out.