Not to be deliberately difficult but surely "I like Rachmaninoff very much" is a different statement than "Rachmaninoff is a radical"? There's surely plenty of pieces where nobody would even begin to argue that they were radical (even in their time) that can send chills down one's spine.

(The counter-argument might easily descend into "all great art is radical" I suppose the article itself touches on this: "At these colloquies, someone inevitably proposes that Composer X is more of a modernist than had hitherto been suspected." As a huge fan of the Vaughan Williams symphonies, I'm rather familiar with this trope)