But the planet's androids were based on the crew's thoughts and expectations, as read by the planet. Finnegan and Ruth acted the way Kirk imagined them, the Rigel II cabaret girls acted the way McCoy imagined them, etc. So it seems more likely that a person of Japanese heritage would default to imagining a generic samurai as a hero rather than a villain.
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On the other hand, McCoy was "killed" by a Black Knight because he cast himself as a white knight protecting Tonia Barrows, and the planet gave him a suitable opponent. So it's possible that Sulu imagined himself as a heroic samurai and the planet sent a more antagonistic one after him. But that seems incongruous given that Sulu was otherwise always played as entirely Westernized in his interests, more likely to dream up Cardinal Richilieu as his adversary. It was just about the one time TOS went the Asian-stereotype route in writing him, and the only time it linked him to Japanese culture in particular.
