Earlier quoted context omitted.
While a great plot point that is entirely fantasy and fiction. The average IQ rate of every generation tends to be a few points higher, though there may be a cap. https://en.m.wikipedia.org/wiki/Flynn_effect
The Flynn Effect is actually no longer observed. [0] There is a multi-decade IQ drop in multiple European countries with otherwise world-leading Education systems. More interestingly the drop is also happening intra-family which defeats the initial theory of a dumbing down of the gene pool. Currently the best theory is that there is an environmental cause. If I'm allowed to speculate my money is on diesel engine NO2…
The study underlying that CNN article only used three decades of data and only for Norwegian males. Also note that their cohort IQ delta is < 2 points across a decade which is well within error margin.