Probably because, as noted when you asked, this does not affect actual color rendering, names used by voice assistants, names used by predefined color pickers in apps, or really anything other than the value of the (calculated from hue and saturation or color temperature, but otherwise basically read-only) colorName attribute in the UI.
Thus, the effort is not worth it for most people. 
Lights do, indeed, vary, and perhaps this could be tuned for some know to consistently differ. But the reward for that effort just isn't there IMHO.
