Blue could represent playing around your opponent, or tempo.

Most of blues toolkit is about reading theory (draw and filter effects), direct action (counter spells and bounce effects), opsec (evasive creature effects), and Lenin busts (artifact synergy).

At least in terms of the blue stuff that makes it into core sets more often than not (core sets used to be a thing and were meant to represent the a beginner friendly jumping-in point, closer to magic as Garfield intended than the rest).