Yes, you are right, I will soon accept a list of rules about this topic. Sorry for the difficulties.
ThePC007 makes sense. Do you agree that the following is a black and white image?
... or would you count each antialiased pixel as a separate color? Antialiasing is a very small amount of pixels used to stop the art from looking like trash, not a way to circumvent the rules. The image is black and white. Also there is no way to replace antialiasing with dithering.