sevs, I have no take on "The Rest is Noise" because I never heard of it.
Re, Mahler ,after 60 years of listening to Classical my take is my time is better spent with Brahms or Bruckner.
That said, his "Das Lied von der Erde" is one of my favorite pieces .
Might not be if I didn’t speak German.
Ditto with Stravinsky, don’t care for him much either yet his "Pulcinella Suite" is another favorite of mine .
No rule that you have to be in love with any great composer, save Bach of course, Music is like women , you like what you like .