it says more about the author than the music

A frequent response to negative criticism, but one I don't really understand.

"They played a blues in F. Then a variation on rhythm changes clever enough to prove there's still life in that old method." "XYZ is possessed of a fine technique, but thanks to an unforced modesty, it never eclipses melody and feeling." Do these sentences tell us more about the player or the listener?

I can't tell you much about music, but I can tell you about myself. In fact, I think music is fairly rarely talked about - see any feature-length article on a musician in, say, the NY Times. If music is not fully contained in either its technique, its context, its consumers or producers, is it possible to talk about it, or only around it? Obviously, if music's artistic space could be fully duplicated (in words, painting, film, etc.), it wouldn't have much reason to exist.