having read your linked article, it doesn't seem so much that her conclusions were incorrect but that she exaggerated (intentionally or unintentionally) their impact. Expanding on the subcomponents of big five traits like conscientiousness seems like valuable work to me. Nonetheless when I'm reading self-improvement books I always take the claims with a pinch of salt because most of them over-hype their contents anyway. I'm still finding the book interesting and educational nonetheless.