I'm going to take issue with that last paragraph. Why take a shot at Katy Perry for putting out formulaic pop after spending the entire review praising Foo Fighters for formulaic rock. Although you use different language for both, Foo Fighters have been on autopilot since they broke into the mainstream. These guys have literally been putting out the same brand of single-drive radio rock albums every two years since before most of us even listened to music. Foo Fighters aren't "filling a void," they're playing into it. Take away the guitars and drums and replace them with synthesizers, put Katy Perry in Grohl's place, and I guarantee no one would tell the difference. Take Katy Perry's "Extraterrestrial" and change the instrumentation around, put Dave Grohl in front of the mic, and it could be a Foo Fighters song (given it'd need different lyrics).
I'm not attacking you so much as I'm taking issue with your seemingly random praise of one artist for being mainstream while taking a shot at another for doing the same thing. People want to sing the chorus of "Fireworks" because it's a huge, homerun of a pop chorus, the exact same kind of choruses Dave Grohl has built his career upon.
tl;dr Foo Fighters = Katy Perry
That was rough to read. Foo Fighters may release the same sorta music with each release but it is consistently good. Not every song makes it to the radio and the ones that do should be praised because real rock is scarce on the radio.A shot at Katy Perry or not, Foo Fighters have a discography that fans can get by. A pop formula that pop stars use these days will not last them forever.
Foo Fighters =/= Katy Perry *sigh*