ok, provocateur!
Blaming Sonic Youth for nostalgia in music is just silly. All music is a network of references to other music. Musicians, like other artists, copy each other. Like other artists, they borrow from and pay homage to contemporaries and predecessors. Most great musicians are also great lovers of other people's music
Sometimes people into indie-rock are so into novelty that they like stuff just because they think it dispenses with conventions even if it sounds terrible (like most of uber-hip Dave Longstreth, who just seems like a Saturday Night Live parody of earnest folk-rock to me: http://www.youtube.com/watch?v=XdT0N4GOydo). Can't decide for themselves what they like? Have no aesthetic criteria except what other people say is cool? That's why I think a lot of these hipper-than-thou music fans describe the most vanilla, hackneyed pop-drivel as if its genius, &/or praise to the skies some completely amateurish indy act who will disappear in a few years and while dissing Sonic Youth for being past their prime.
As for the ATP "Don't Look Back" concerts - I've seen the criticisms but I don't agree. Maybe it's because I'm older than most of the other folks at the rock show, but I don't see what's so bad about enjoying music that's all of twenty years old. Maybe it's even more nostalgic to insist that classic records can only be enjoyed in the CD player and never live (unless remixed or re-imagined by some youngster). the Don't Look Back shows that I saw at Pitchfork fest in 07 and 08 were great.
Thurston Moore also joined another elder, Yoko Ono for "Mulberry" the following night when she headlined. Too bad the Stooges' reunion was lame. It's not true of everyone. Public Enemy's performance of "It Takes a Nation of Millions" in 2008 was fantastic and energizing. see: http://www.youtube.com/watch?v=LvSc-XQflek&feature=related