Fashionable composer Thomas Adès, whose Powder Her Face and other works are considered by some to be in the mushroom category themselves, calls Wagner a "fungus":
I don't find Wagner's an organic, necessary art. Wagner's music is fungal. I think Wagner is a fungus. It's a sort of unnatural growth. It's parasitic in a sense — on its models, on its material. His material doesn't grow symphonically — it doesn't grow through a musical logic — it grows parasitically. It has a laboratory atmosphere.
In an interview with the Guardian, Adès goes on to talk about an apparently more important composer:
The music we listen to is the residue of an endless search for stability. I think you can make a sort of illusion of stability in a piece; you can fix it in a certain way. In a musical work, you permanently fix something that in life would be appreciable only for a moment. If I put a note under the microscope I feel I can see millions, trillions of things. In Polaris, my recent orchestral piece, a "voyage for orchestra," I was looking and looking at a particular C sharp, and as I put it under the microscope I saw or heard a writhing that turned into the piece.