IQ is more highly correlated with life outcomes for people with below average to average IQs. Most career tracks have an IQ floor, and if your IQ isn't high enough to meet the floor level, you can't perform that job adequately. Few career tracks have IQ floors much higher than 115, so if your IQ is higher than that, your parental wealth and connections become very important.
Thus, the higher your IQ, the more important the wealth of your parents becomes (the very opposite of what most people think). People with exceptionally high IQs but inadequate parents often have poor life outcomes because of the mismatch.
So, JFK and GWB would be examples of people just above the Presidential IQ cutoff who became Presidents because of their fathers.
In general, let me say that I check in on Half Sigma regularly because, while we have fairly similar approaches, he often winds up with ideas I wouldn't get to myself.