I'm not clear where the difference lies between dismissing Adès or Stockhausen, Tavener or - who? Mendelssohn/Brahms/Tchaikovsky, perhaps.
I think it's a good rule never to be put off listening to music you haven't heard by the negative report of any other listener, as their taste in music is rarely likely to coincide exactly with your own.
I quite agree that such an article in the Guardian is a "good thing" and that it will dispel myths among some audiences who haven't even heard enough of it to 'dislike it'. The term 'classical music' is frequently disputed (I'm rather surprised that TS used it - if he did (can't be bothered to check whether he did use it or whether it was a sub's addition) ). But the painting comparison hardly holds as we don't speak of 'classical painting' in that way anyway. The term would surely refer, for example, to works by Poussin, Le Brun and similar schools, not to Delacroix or the Impressionists.
You say: "There isn't much that's "contemporary" about Adès,", but, in music, at least, I find it difficult to understand what critics would intend by the term if it doesn't include the works of a range of living composers, of whom Adès would be one but Tavener might not.
If one thinks of music of the past, it was always "contemporary", insofar as one can "age" works by, say, Purcell, Mozart, Mendelssohn, Wagner, Ravel, Schoenberg or Stockhausen, and even those composers contemporary with them who composed in different styles, because each of these particular figures added something to the received idioms, respectively speaking, even at the same time as incorporating trusted principles of construction from the past.
The fact that, since the demise of atonality as a defnining characteristic of 20th century modernism, the revealing of this "dependence on the past" now seems to loom so large in "contemporary classical music", sometimes under the rubric of "postmodernism", with commentators prone to statements to the effect of art being, in a manner of speaking, perpetually condemned to recycle principles deemed intrinsic to itself, speaks to me of a lapse in confidence in a hopeful future - one in which humankind is eternally condemned to repeat the mistakes of the past and never learn vital lesons of history.
I remain to be persuaded to the contrary. Any offers welcomed!
I don't really understand why it seems to be expected of every composer that s/he contributes something new and original to musical composition, I mean apart from what is distinctive in terms of his own personality. There are of course ground-breaking composers such as those you have mentioned but for each of those there are many more that are not and that has surely always been the case - those composers providing the background idiom for Mozart for instance. One of the unfortunate consequences of concentrating only on the ground-breaking composers is that a large number of very fine composers have been extensively neglected (as Suffolkcoastal's researches show). Surely it is possible for a composer to contribute meaningfully by providing music that is recognisably his or hers and not anyone else's, without necessarily providing revolutionary advances?If one thinks of music of the past, it was always "contemporary", insofar as one can "age" works by, say, Purcell, Mozart, Mendelssohn, Wagner, Ravel, Schoenberg or Stockhausen, and even those composers contemporary with them who composed in different styles, because each of these particular figures added something to the received idioms, respectively speaking, even at the same time as incorporating trusted principles of construction from the past.