I would say it's because none of the women you've listed, great as they are, are as threatening as Swift. She might just be pop music to some, but she's a powerhouse in the music business too. She's got wide range appeal with fans that span decades, millions and millions of social media followers (probably more than all the female artists you've listed combined). She's changed the face of music business and she was winning grammies in her teens. That is all very threatening to the good old boys. When you look at someone's worth, it's not just the money they make, but the overall influence they have too, and Swift weilds A LOT of power, so little men with fragile egos are scared of her.