Yup. I had the same revelation when I learned that many of the colors we perceive don't really "exist". The closest thing to hue in nature is wavelength, but there is no wavelength for purple, for example. The color purple is our visual system's interpretation of data (ratio of trichromatic cone cell activation). It doesn't exist by itself.

It's the same reason that allows RGB screens to work. No screen has ever produced "real" yellow (for which there is a wavelength), but they still stimulate our trichromatic vision very similar to how actual yellow light would.