The "go back to your coffin" comments need to take a hike. Madonna's not an elder, she's in her 50s. Consider your comments when there are likely people in her age bracket reading them. The idea that you should be limiting or censoring yourself with age is a terrible message and isn't healthy for anybody.
Of course it's jarring seeing her with a grill and twerking and whatever because the pop stars who do that tend to be in their early 20s, but who cares. She does it just as well, and she's a great dancer. And there's an air of irony and irreverence to everything she does that makes it extra special I think. My problem with her stems from the fact that most of her material feels very derivative of more authentic music that came before it, but that's been my problem with her since she started. I guess Rebel Heart feels especially deriviative because she's older now and people can't help making a point about it. Come for the music if anything, not her age.
That said, Rebel Heart is not very good. lol