I think you have put your opinion across very well, but somehow doubt either ladies will take any notice of you, nor will their record producers cuz whether you like 'em or not, their music still puts the pennies in their banks.
(personally, I shall still be enjoying both their music til I am carried off in my pine box, but then I still like Perry Como and Cliff Richard, so who am I to say?).

"time to move on and let people appreciate real female talent - beverley knight/duffy/estelle"

I don't get it - what's stopping you appreciating these other ladies' music? You dont have to listen to, or buy, madonna's or kylie's if you dont want to.

Why should they 'move on'? I've never heard of beverley knight or duffy, and dont really know or like estelle. But i like madonna and kylie.

Isn't there room in this world for all kinds of music, not just the kind you personally like?