There's something I like a lot about Shostakovich's popular works (Fifth Symphony, Eighth String Quartet, Tenth Symphony) that isn't really discussed in criticism or scholarship, which usually focuses on his music as political, biting, sarcastic, etc: the sheer badass factor. There is a reason that high-school students at music festivals swoon at the finale of the Fifth or a hair-raising performance of the Tenth. The music is, quite simply, badass. Listening to the second movement of the Eighth Quartet, you hear the notes zoom by. In a recording, one can still feel the physical exertions of the performers.
Even if it's music written for the victims of fascism, or the victims of Communism, or whatever the current vogue about Shostakovich's political feelings is, it's music you can pump your fist to. It is visceral in the truest sense of the word. We watch the amazing videos of the Simon Bolivar Orchestra executing the Tenth Symphony vigorously not because the piece is beautiful or profound (which it is), but because it is awesome to see these incredible kids sawing away on their instruments.
Conventional scholarship and criticism of the Tenth would talk about the kind of forced victory and sarcastic, mechanistic aspects of the piece. But the most immediate thing, the first thing you hear in the second movement is how fast and badass it is. That's clearly what is on the minds of the performers as well as Dudamel. He is successful at conducting a piece like this, less because he identifies with Shostakovich's political horrors, and more because he knows how to go balls to the wall when necessary.
Badass is also a factor in Mahler, which leads to plenty of aesthetic debates (I use that term very loosely) with friends. There is a school of thought which ascribes the greatest moments in Mahler to be loud and bombastic--and by a school of thought, I mean brass players. When my scholarly wisdom argues that the heart of Mahler's Seventh is in the creepy modernity of the two Nachtmusiks, they counter that you can't beat the dramatic baritone solo in the first movement or the trumpet opening of the fifth. I'm not sure if I actually like the middle movements more than the outer ones. It's hard not to succumb to that kickass trumpet solo. Sometimes I just feel like I'm toeing the party line for Schoenberg and the modernists, who saw those Nachtmusiks as precursors to atonality.
This argument dissolves in a work like the Ninth, which, rather than being dominated by brassy climaxes, is haunted by the ghosts of them. What appears to be a trumpet climax in the first movement is quickly dissolved by lush strings. The Ninth may be my favorite Mahler symphony because of this. Mahler strives for climax, culmination, even apotheosis, but will suddenly suppress himself. The result is powerfully emotional and a different zone of feeling from the almost-arrogant, youthful climaxes of the Second (my other favorite Mahler symphony). It would be a cliche to say that death was knocking at his door when he composed the Ninth--when was Mahler ever not thinking about death?. Perhaps modernity was knocking. He attempts to retreat into the brass-laden climaxes of his younger days, but fails. The trumpet, rather than soaring up like in the opening of Seventh's finale, crackles away. Musical badassery fades from the German stage (Schoenberg and Webern fragment it in their aphoristic piece for orchestra), only to re-emerge a few decades later in Russia.