She's not a megastar at all, she's having her moment, just like Lady Gaga and others before her. She's just very lucky, she has an amazing team who knows what they're doing, and as I mentioned before, music is consumed differently these days. Sitting in bed listening to a song on your phone isn't really a pure sale, it's kinda fake in my opinion but it is what it is.
Madonna is beyond a megastar, she's iconic and legendary and her crown won't be taken away by someone with a personality of a cabbage, no matter how many records of Madonna's she's desperate to break.
End of....