The music industry's disappearance won't create a void, things will move in to take their place.
You don't need the big labels to be the filter, there are plenty of other individuals and companies who will take that place as the arbiters of "popular" music.
Big labels aren't even filters? They're creators. Without them we'll have no popular music. Where were Lady Gaga, Rihanna, Britney Spears, Ke$ha, Justin Bieber, .fun, Taylor Swift all before a major took them on? Nowhere. Flopsville. They create mass market products. Without them nobody will have the budget or knowledge to do it. And that'll be a sad day.
Joustin Bieber was a youtube sensation before any label hired him.
Great operas existed before the record labels... when they are gone musicians and theater and performance directors will continue to produce great art.
You don't need the big labels to be the filter, there are plenty of other individuals and companies who will take that place as the arbiters of "popular" music.