SilverArrow20XX
Walks in the Light of the Crystal
Read what you wrote, you're saying that having darker skin ("roughness") is unbecoming of a princess. That is exactly the problem and I doubt you actually believe this.
I'm saying having a worker's tan is typically considered unbecoming of a princess. As is having calluses, split ends, unmanicured nails etc. They're also expected to behave in a dainty manner. Gentle body language and speech patterns. Tetra also does this after transforming.
That is a different thing than having naturally dark skin. A princess with naturally dark skin, is still typically expected to have immaculately cared for skin, devoid of signs of manual labor, and still behaves in a dainty manner. The only difference is that sun tans are much less apparent on naturally dark skinned people.
This is the princess stereotype the game uses, and is also the basis for the stereotypical feminine standard of beauty. This is its own problem, and I don't agree with it. It's different than "dark skin = bad" though. It's more "feminine = delicate".