My point, which I'm not sure if you got so forgive me if you did, was that unless all your TVs have been 1-bit monochrome, each RGB pixel represents a 3D vector space all by itself. Your "3D" TVs are actually 7D!
And since we're being pedantic, white cannot both be "a color" and "all the colors" at the same time - in fact it's never "all the colors"! We are either using "color" as a shorthand for wavelength, in which case there's no such wavelength (yet merely 3 are sufficient to produce an impression of white, certainly not all of them), or "color" means the subjective impression produced, in which case the various shades of white comprise a narrow subset of these.
Did I mention I was pedantic? :)
