^ Nothing. People just like to throw other top female acts into the mix as if they have anything to do with each other. Just kidding.
Though it's also possible they're using those acts as a reference for what Ayu should strive to do. However, if Ayu did that, she wouldn't be Ayu. And I wouldn't really want Ayu to try to be Kuu these days
Kuu's still finding herself, too.