Why have americans become so anti-british about music since the 1990s? was it the spice girls 'wot dun it'?

I don't think it's ANTI-British, I think it's just that the British music scene isn't quite as good as it was in say the 60's. And I'm not bashing british music. American music does the same thing. It fluxuates. It's at a height right now and I'm sure in the next decade it will decline and again will rise the Brits.