This is a ridiculous statement. Listen to Embryonic. Quite the opposite of any type of "high profile cover band". That album proves how legit they still are, and how much they don't give a fuck about getting on the radio, or selling 1000000000 copies of their album. They just enjoy making good music.
And its not like they are trying to duplicate Dark Side. Its a cover of Dark Side in the Lips crazy style of doing things.
You must have never been to Flaming Lips show either or you would DEFINITELY not be saying "they've stopped trying"
Although I do agree that Bonnaroo has lost a lot of what used to make it awesome.