No, I think you are misunderstanding. IQ does not describe the likelihood of someone being that smart. It just means you order a number of people by their „intelligence“, the one in the middle is defined as 100 and then it depends on how many other people are in that line which IQ number the person at the end of the line gets. So it’s impossible because the definition of IQ is such that a certain number doesn’t come up without a certain number of measurements.
It‘s as if you would say 150% of all people are female. That is impossible, not just unlikely.
If you just take the statistical definition of IQ and run with it, AFAIK the smartest person alive will be at something like 190 IQ. If you really run with it, the smartest person that has ever lived should be around 200.