Does some artists not realize that pubic hair is the same colour as the hair colour?
Is it? This begs a quick research. Okay, did a quick research. It seems the color of pubic hair is closer to the color of the eyebrows than of the color of the hair, being sometimes darker or lighter than hair color. So, I guess you are right, the pubic hair shouldn't be all black in this picture.
I thought the question "Does the carpet matches the drapes?" came from the fact that not always the hair color matches the pubic hair, but it seems it's about dyed hair.