Aside from directly contradicting itself in the next sentence, ChatGPT is also guilty of an anachronism in the last two words. IN 1956 acting in a role outside your "culture" (by which is meant race) was common enough, and then no one would have even though of finding a Mongolian to play the role.John Wayne did not play Genghis Khan in any film. However, he did star in a film called "The Conqueror" in 1956, where he portrayed the character of Mongol conqueror Genghis Khan. This casting decision was controversial because Wayne, an American actor known for his Western roles, was not of Mongolian descent, and the film received criticism for its historical inaccuracies and cultural misrepresentation.
Digression: This film demonstrates the poor acting ability of one of Hollywood's "Greatest" actors of his time. Contrast this with Orson Well's or Olivier's Othello; Yule Brenner's King of Siam in The King and I, or just about any role which calls upon actual acting skill to pretend to be another person. Wayne was never enyone else other than Wayne.