a public service announcement
Thanks a lot, SCAD professors who forced me to buy Cadium Red, Lemon Yellow, and Ultramarine Blue for class.
Not that simple.
CMY is a subtraction process. The reason your printer has CMY pigments is to mathematically do CMYK to RGB (colors of light), you see the in that previous image. The K part is black for actual black, because CMY pigments process black isn’t BLACK it’s more like a very dark green.
RYB use requires adding white or black, That’s why the edges in HSL (Hue Saturation,lightness) are towards white or black. PRINTERS DO NOT HAVE WHITE INK, nor can they tell what you’re printing on.
CMYK only requires black for true black. Hence this is why cheap injet and color laser printers are CMYK.
However more expensive printers actually use two Cyan and two Magenta, one that is “whiter” than the other.
You also have to take into account what you’re printing on. The types of color needed for “bright white” laser printer paper, canvas and clothing are not the same.
So contrary to what the image in the OP says, it’s not that simple.