I agree with your reflection about what sex appeal is, but I must be honest and I say that I can see why many people find her sexy. We must consider that the majority of people don't stop to wonder whether a picture is photoshopped or not, neither they seem to bother about class and elegance (that I think to be some of the main factors for which I consider someone sexy). She's just too plastic, fake and tacky for my taste but I can see why the average public considers her sexy.
True, for the average male or female she is the dream unfortunately.