well, it is your personal opinion and you seem to have high expectations, but again
she is not here to please me or you, she is just doing what she feels like doing. And most of us seem to be liking it almost every time(well, I am less and less impressed with time but we all mature), The fact you do not find her material mature enough to keep you interested might mean that you are much more mature now and it is a good thing. Entertainment is not about giving you life experiences, it is about giving you fun and fantasy. She is not a rebell anymore and she does not need to be. Rebells are normally people who are not mature enough to see the real game and raise their voices. She is more than mature and has a lot more life experiences(most of them amazing and much deeper than at the beginning of her career), which does not mean she must inply them all in her work as an artist. She is just having fun with it. If we need a deeper experience, we should never look for it in the work of a famous entertainer
) But if you really want to find it somewhere, try the music of Sinead O'Conner