They can't tell you why preferences are different. It is all implied. A much more straight forward explanation is that developed countries have long histories. To become developed you need to have developed industries for a long time without too many wars. The idea that the preference of Indian women, were many industries are being developed as they get into job market, is remotely comparable to the preference of Swedish women were industries have already been developed for centuries isn't credible. It simply isn't an equal comparison. Yet, that is exactly what people are drawing these conclusions from.