What ends up distinguishing Shogun as something that falls into the trope is that it is a white protagonist, half the book is about his personal change, and that it is probably most people's first and only look at pre-Tokugawa Japan. Which, again, may not be what Clavell intended, but it still happened, much like Arthur Golden and the geisha.

Ergo the problems inherent in cultural appropriation, particularly when art by the dominant culture about the minority culture usurps the minority culture's representation of itself in the dominant culture.

Whereas with Le Guin, the representation of Gethen in fiction isn't really a political statement with real-world repurcussions for Gethen people.