Sliding Scale of Realistic vs. Fantastic applied to Human Skintones
Human skintones in Real Life are described as varying shades of beige and brown, such as ivory, tan, almond, caramel, and teak.
The above are sometimes exaggerated into various warm, bright colors (not the real skin tones the colors are used to describe), usually yellow, orange, red, pink, black, grey, and white.
However, the above colors are common in Amazing Technicolor Populations because they are not outright "unnatural" (and often cooler) colors like green, purple, magenta, blue, and cyan.