It's interesting though isn't it, because if she contracts someone good, the ghostwriter does an excellent job of imitating her style, then really you do get exactly what you wanted? I don't like the idea of it either, fwiw, but it's hard to rationalise.

There is nothing hard about rationalizing this. If this was what "I wanted" they would just put the ghostwriters name on cover with "written in style of X" in bold letters.

But, it is not what people wanted and they would buy the book less.