My first thought with your post was that you missed the 60s ... and wasn't that
a grand narrative? :)
Ken, you may have to help me out here because I had a bit of a breakdown in the mid-90s and stopped playing from the late 90s through to 2007.
My impression as a non-musician at the time was that the 90s were mostly about globalisation and the 00s about technology. Governments - shifting heavily to the right - have increasingly handed power to giant multinationals, and they have taken on the role of our (tacit) unelected leaders.
Just today our nation's leader was removed after proposing additional taxes on mining companies ... they have high foreign ownership so our PM was trying to get Oz a greater share of the non-renewable resources being dug up at warp speed. The companies' and their (well-funded) public campaign saw him sacked. He made the mistake of not reporting to his corporate masters for veto before enacting policy.
The rise of the Net in the 00s has seen a greater increase in the influence of the media. Increased commercial influence is inevitably reflected in the arts. All this points to homogenisation. Music is increasingly technologically based and produced more cheaply and efficiently, with songs spending their short lives trapped in the battery hen cages of mechanised beats before being rapidly replaced by another on the production line to serve wired young people leading largely digitally-based lives (there was an extended chat about this in the Drummer vs Computer
Sorry, more musing than grand narratives :)