Please don't devolve into reactionary nonsense. I'm pretty sure that if you measure the average IQ of good (whatever your definition of good) chess players, you won't get 100.
Seems weird to dismiss stuff as "nonsense" just because you're "pretty sure". Hikaru Nakamura (who's been the world #2 in classical rating) did an IQ test on stream and ended up with 102. I've not seen any other results for top players.
The first study of it I found (https://www.sciencedirect.com/science/article/abs/pii/S01602...) notes that, while there is some correlation, "Full-scale IQ explained < 1% of the variance in chess skill."