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.
A lot of it is bluffing, like in Poker.
If you get to that level, you know all the strategies and moves.
It’s all about tricking someone into making a mistake.