Halle's cover look will re-create a 2000 issue that featured former President and non-Obama supporter Bill Clinton.
Unlike former actresses chosen for this issue, Halle's cover wasn't preceded by a months long campaign revealing photos of various body parts with clues inviting readers to guess who the the sexiest woman is. It's not like magazines aren't familiar with whitewashing a model's color away with lighting and Photoshop so I don't see how Halle's brown skin would have been a give away.
Maybe TPTB at Esquire just don't think a black "sexiest" woman is worth the hype.