There’s nothing about the entire topic I find interesting enough to even comment on. I appreciate the fact that you have introduced an opportunity for any of us to engage in a meaningful conversation about it, I will have to decline. Sorry. ___
I will whip out my favorite answer to questions like this: It's complicated.
I think it is almost inarguable that KKW and the art directors are trying to invoke images of other African-American celebrities. When I look at the picture, I think of pictures I've seen of Diana Ross, Tina Turner, or Pam Grier.
Now, for some history and context. There is a long legacy of places where Europeans invaded/colonized/subjugated other cultures and ethnicities that looking/dressing/speaking/behaving like the European dominators becomes the cultural ideal, because the Europeans and their descendants are the people with wealth, power, and social status. This can be seen quite clearly to this day in Latin America (cf. Bolivia's Evo Morales and the recent coup to overthrow him), but is common in many places.
This phenomenon even extends to beauty standards. In places where Europeans come to dominate people who look very non-European, it's the European-looking people who appear on magazine covers, on TV shows, acting in movies, etc.
So that's one context informing people's reactions to the KKW picture.
Another is the long history of American mass media culture playing fast and loose with race and ethnicity and who gets to portray whom in visual media. Actress Rita Moreno (who is Puerto Rican by birth) made a career out of playing "ethnic" roles, playing everything from Pacific Islanders to African-American characters. In recent years, there has been controversy over movies like "Ghost in the Shell", where Scarlett Johanson played a nominally Japanese character, and the movie "Aloha" where white-as-a-roll-of-Charmin Emma Stone was cast as part-Chinese part-Native-Hawaiian character.
The obvious question some ask is, if a movie or TV show or other visual media has a Pacific Islander character, or a Japanese character, or a Native American character, why don't the producers hire someone of that ethnic heritage to play those roles? Why the force-feeding of "white" actors or models into those roles?
Finally, the purpose of most visual presentations like the controversial KKW photo is to sell the consuming audience the idea that the portrayal represents a beauty ideal to which the viewer should aspire. Of course, very few women look like KKW when she's photographed with perfect camera angles, perfect makeup, perfect hair, perfect lighting, and perfect Photoshopping to eliminate any visual flaw that makes it through all the other perfecting processes. Such presentations are made to make the audience feel bad that they don't look like the ideal, so that they will consider purchasing the products of the many advertisers who are sponsoring the visual presentation. The implied message is "You, too, could look like this, if you'd only by the products we're trying to sell you."
Given that notion of such images presented as a beauty ideal, and the history of beauty ideals being Euro-centric,and the history of having ethnic Europeans being used to portray "ethnic" characters, I can see where people would object to the KKW picture.
Their reaction might be along the lines of, "Wait a minute. All this time you've been selling us on the idea that European-looking people are the beauty ideal and that people (esp. women) with African features are 'a bunch of nappy-headed hos." So, not only are you suddenly flipping the script and selling Africanesqe features as a beauty ideal, but you're using someone who isn't of African background to do it? WTF?!?!?!"
Are the terms "cultural appropriation" and "blackface" appropriate descriptors for what is occurring here? I'm not certain. It depends upon how you define those words. But is there something at least a little sketchy going on with this presentation? I think there's a good case to be made.