Here's why he uses them:
* His Deck's Theme: Yusei's main deck theme is "Speed Duel," emphasizing fast-paced and aggressive gameplay. The "Speed Warrior" archetype fits perfectly with this theme, allowing for quick attacks and powerful plays.
* Speed Counters: The core mechanic of the "Speed Warrior" archetype revolves around Speed Counters, which are gained by using certain cards and allow for powerful effects. These counters offer a unique way to gain an advantage and control the pace of the duel.
* Versatile Deck: Yusei's deck isn't solely reliant on the "Speed Warrior" archetype. He also utilizes other archetypes like "Junk" and "Synchro Monsters" to enhance his strategies. "Speed Warriors" serve as a key component within a broader deck strategy.
It's true that Yusei relies heavily on "Speed Warriors" for his aggressive plays, but he's also shown to adapt his strategy depending on his opponent and the situation.