-And, lol, IQ is a rather sketchy metric for measuring intelligence. It's not only statistically skewed to match sample groups, where 100 IQ in 1900 does not mean the same thing as 100 IQ in 2020, but there is no universal IQ test and people bicker and argue over the validity of what an IQ test is supposed to measure and whether or not someone should or can improve on them from studying. It just really doesn't mean much. But whatever fine, I guess.
Generally a typical IQ test measures logical-mathematical inteligence, spatial inteligence, memory performance, etc. Differences on numbers might be due to more sophisticated methods of measure. Training for IQ tests might create a superior result on a general difference of 10 points from the original result, and with being technical careers more intensive in logical-mathematical or even spatial intelligence (practically a good training for the average IQ test) philosophy students for example have an average higher IQ, which is indicative of a general higher IQ despite training (aka have a general stronger mental capacity for short term and long term memory, logical-mathematical intelligence, etc). Furthermore, measuring intelligence by IQ or other intelligence testing methods is far above and superior to going for what degree is harder to get, or what you subjectively value, specially because (in my opinion) harder to get means stronger effort and not necessarily more intelligence. IQ will evidently not measure how stupid someone can personally be, but his capacities, and someone of higher IQ but the personality of a donkey will behave or speak as a donkey despite the IQ scores, which wouldn't change the fact that when it comes to the competencies measured by IQ tests he has a higher capacity.