As the title states, no artist can ever offer a single standard interpretation. As many are aware, many artists have re-recorded pieces i.e. Claudio Arrau with Beethoven, Herbert von Karajan, Pierre Boulez with Debussy, Webern, etc. With this in mind, it is quite strange that Pierre Boulez has come under attack for his interpretations of Mahler's works. So far I have only heard Otto Klemperer's rendition of the MAhler's Ninth, Karajan's and have yet to listen to Barenboim's. As is evident, each of these are different to each other, and Boulez definitely does not resemble anyone's. His command of the orchestra is amazing, the sound he produces and atmosphere that is created as a result is admirable.
Many may prefer other versions, but to say that an artist's rendition "doesn't work" does not apply. I am a big fan of Klemperer, no matter who he 'interprets', yet Boulez is an amazinf conductor and an artist most of all who has a particular aesthetic.