U get tons of attention deficit(ADHD) if u play too much "strategy games", than no matter how high ur IQ is if your attention become weak, u will seems dumber or a "slow person" on real life, high IQ is useless when ur brain got tired.
But hoi4 is very chill like playing chess, few attention intensive compared even to older RTS/strategy titles, thanks to its design and UI.
The great offender in other games is the micromanaging, i reminded "empire earth" franchise, where u have to click on individual aircrafts to get them on carriers, lolz....