What do you think was problematic?
In the chapter provided, the author is repeating the ideas from a different text while giving picture examples of those ideas that she's assembled herself. So, it's not surprising that I found the ideas in the text to be mostly fine, but the examples are where I would not recommend this book (this chapter, at least).
Her "beautiful" examples almost always include high-heeled shoes which I don't support. Any history of heeled shoes for women is basically a list of shifts between status symbols, vanity, and sɛҳuąƖ appeal. Combine that with how terrible they are from a health perspective, and I'm not going to recommend anything that says flat shoes are frumpy and heels are beautiful. If anything, the preference should be the other way around. To be noted, this idea isn't as much emphasized in the actual text as it is in the images.
Also emphasized in the images is the idea that a beautiful outfit equals a shorter skirt and only in winter should we need anything that falls significantly below the knee. Given the number of images, there are a couple of exceptions to this pattern, but frequently the comparison between "frumpy" and "beautiful" is accompanied by a shortening of the skirt. In order for her examples to be relevant, she needs to have more apples-to-apples comparisons -- a long skirt with an inharmonious pattern should be compared to an equally long skirt with a harmonious pattern. Instead, the idea that shorter skirts create more beautiful outfits is prevalent, and she does not fashion those skirts with tall stockings as the would have been done in all of the eras she describes wishing to imitate.
Those two were my biggest issues, but even apart from that I think this text would have a very limited audience. Most people are forced to find clothing based on economics and not aesthetic value. It's already quite difficult to find anything modest on a limited budget and I wouldn't want to spread the idea that basic modesty isn't good enough for day-to-day wear.