Didn't see much, if any, 1969-realted stuff in 1999 (though it was very much around in 1989).
Hell, even Woodstock 1999 was almost deliberately void of nostalgia from the original.
Didn't see *any* Sex Pistols/Ramones-related stuff in 2007.
30 years is a looooooong time.
There really is no reason to spend much time on what Nirvana did 30 years ago, except because now that we're old enough to remember stuff that happened 30 years ago, it doesn't seem all that long ago.