The issue is the way wow textures work. The reason the new Human faces are limited to specific colors is the same reason we donât have armor/weapon dye. The textures have the colors baked in rather than being able to dynamically take color from a color wheel. And Blizzard only bothered to make three skin color textures for each of the new Human faces.
So the reason you see only some faces being able to use some skin colors is because every skin color for every face is its own texture. For every face to be able to use every skin color they need to make a texture for every face in every skin color. That takes time, and Blizzard ran out of it prior to Sl launch. It would save Blizz so much time adding new customization if they switched to dynamic textures (and we could have dyes) but that would necessitate a huge upfront investment of time and money to do. I donât think Blizzard sees the return on such an investment to be worthwhile.
Thatâs not to say Blizzard shouldnât do it because they totally should, but I get that they ended up cutting corners to get Shadowlands out, and are still behind apparently. So much for the artists being âaheadâ so they could spend time make the tree mount. Personally I would have rather they made more customization.