Why do the best chess players in the world play classical chess isn't rapid slow enough for them if they understand the game so well?
Because you can get into much more depth in a slow game. And it also requires more mental endurance. At the end of a tough slow game, the players have been through hundreds of deep calculations in their heads and they feel like their heads are spinning a little. And of course, you'll play better chess if given time to unleash your creativity. You will also find it is hard to catch an experienced opponent in a one-two tactic in slow chess competition. Those who win by brute force usually are capable of very deep calculation. It tests your overall knowledge of every aspect of the game; the opening, your tactics, your middle game and positional theory, your endgame skills… When you start gaining proficiency in chess is usually when people start realizing how incredibly vast it is and how much deeper one can always get into it.
idk they should though