Like all gambling games, luck does play a major role in poker, especially in the short term. Poker is different than any other form of gambling, however. Unlike the other games on a casino floor, poker is a game of skill, and the world's top pros make money because they're the best players in the game.
Pluribus's self-play produces a strategy for the entire game offline, which we refer to as the blueprint strategy. Then during actual play against opponents, Pluribus improves upon the blueprint strategy by searching for a better strategy in real time for the situations in which it finds itself during the game.