Sure, playing chess needs intelligence, dedication, and good chess players are smarter than an average person. But it’s waaaay exaggerated in movies. I’m a math researcher, and in any movie, my department will be full of chess geniuses. But in reality, only about 10% of them even play chess.
He was ref this https://www.youtube.com/watch?v=hi5ypuLXnVs
Regardless it’s an insult I wouldn’t throw at anyone other than a fascist.