I agree entirely with simonmoon’s and sturartk’s comments and I see no need to react defensively. simon’s description of Jazz as a genre is pretty darn good. Seems to me that there is a lot of value in being able to accurately describe what it is that defines a genre.
There is absolutely nothing wrong with the classification of music by genre or sub genre, even when the lines get blurred and it has to be done in broad(er) terms. Classification does not, in any way, give any one genre ultimate “superiority” nor “inferiority” as an art form if there is respect for the idea that “there are are only two kinds of music, good and bad”. An idea that, interestingly enough, was promulgated by and is most commonly associated with a Jazz artist. Duke Ellington, one of the greatest.
I believe that sometimes there is confusion about what that idea actually means and was intended to mean. It does not suggest that music should not be classified (by genre), or that there is no value in doing so. Rather, it is about recognizing and respecting the simple fact that in any genre there can be good music, just as there can be bad. There is a tendency on the part of some to put an entire genre of music that is liked on a pedestal higher than that of music that is not liked (understood), as concerns artistic value and validity. Level of creativity and emotional impact are barometers that apply to all genres and keeping an open mind can only be a good thing.