I find it pretty funny that these "smart guys" keep sperging about their IQs- that's not what it's supposed to measure. IQ isn't a metric of how smart you are- it's a means of establishing normal intelligence and how far off a person is from it. The chart goes something like this:
0-20 Profound intellectual disability
20-35 Severe intellectual disability
35-50 Moderate intellectual disability
50-70 Mild intellectual disability
70-80 Borderline intellectual disability
80-90 Low Normal
90-110 Normal
110-120 High Normal
120-140 Gifted
140+ Genius
85% of the adult population is (theoretically) within +/- 15% of 100, and less than 1% have an IQ below 20 or above 140. IQ tests are also notoriously bad at identifying outliers, be they the extremely intelligent or the extremely disabled.
The practical application of it really amounts to streaming in education. If you put kids who will never understand literature or calculus in those classes, they'll drop out. Put them in a cooking class and teach them math for everyday life and some concrete skills and they'll become functional members of society
Similarly, if you have a kid that's way ahead of the rest of the class, trying to hold them back will make them bored, resentful and preform under their potential. Give them more advanced concepts to keep them engaged and they flourish.