>>127008548 (OP)Probably because he always saw himself and his band as an outsider, which they always were compared to the mainstream pop industry, that was until that song.
Suddenly they were dead in the middle of mainstream pop music and that kind of fucked his world view.
At that point you are no longer an artist with a vision, you are just a dancing monkey for the masses and he didn't want to be that. Its probably pretty hard to navigate out of though, as he still has to keep putting out records and the rest of the band probably wants to stay in the mainstream to make lots of money.
Foo fighters are probably what the rest of the band wanted to do ie max money making and he prob wanted to go back to doing weird dissonant shit. So it all fell apart.