I does matter a bit because they were very specific on what features can they do to make Kong's stand out more. Plus, most of Kong's past iterations had brown fur, including the 1933 original, which the posters suggests that the original Kong puppets had a brown coloration, but because it was black and white, people mistook it as always having brown fur. In terms of Kong as a character, having brown fur does making look more unique. But hey, what do I know, I'm still not taking away anything, it's still a cool looking art.