I am not saying you can use the exact same math as in an image manipulation program, these work with different assumptions. Mixing colors in those is usually not correct anyway.

https://www.youtube.com/watch?v=LKnqECcg6Gw

I am saying you can think of subpixels, which already exist, as a form of dithering. Most displays use just three primaries for subpixels - red, green and blue. Their arrangement is fixed, but that is not a limitation of this new technology.