Tuvalu said:
Cyan is just as green as it is blue

Granted. But my particular point was based on Rainbow Dash's fur. She's sky blue - specifically a light turquoise with a darker turquoise outline. Technically, turquoise falls in the cyan spectrum despite not being exactly half-way between green/blue. However, there's over 50 pages of Rainbow Dash currently tagged with blue fur, and 4 images with her tagged cyan fur.

Adding to the confusion is that some artists color her with a truer blue with little-to-no green in the mix, and others go with a true cyan or a mix that has a little more green than blue (particularly in darker/shaded pieces).

The big problem is that while most can easily point out primary and secondary colors, subjective interpretation begins to be used beyond that by the majority that don't care to be more exact than "Purple, Blue, Green, Yellow, Orange, Red."

TLDR: Yes, cyan is distinct from blue or green, but it is still commonly mistagged...usually as blue. And so the point remains that if the tags are kept separate, significant cleanup will be required.