It’s an interesting debate
From the perspective of a Vanilla fan, an NTR game is illogical. Conversely, from the viewpoint of an NTR fan, a Harem game makes no sense...
Both sides present valid arguments, though counter-examples exist for both—meaning high-quality games can be found in either genre...
However, this suggests that, on average, Sharing games are more logical and believable than those strictly focused on NTR or Vanilla. This is because they depict a world where other men are active participants, yet the Main Character can still emerge successful, much like in real life. To be clear, I am referring to the well-executed examples of Sharing games