If Gaga can maintain her desire to be on the stage and has good health she will be around for decades. Like it or not she is not a flash in the pan.
Her popularity is driven entirely by the willingness of Jimmy Iovine to spend money to make her popular. If Jimmy Iovine will get a better return on investment somewhere else, he’ll stop putting her on tv and on the radio, and she’ll stop being popular. She has to be propped up by tons and tons of Major Label dollars. That’s pretty much true with all the Major Label acts these days, but she’s more of a hollow shell than most. Taylor Swift is likely to have a long career, Gaga not so much.