Ok. The idea that Royal or Noble members of Chinese society don't follow fashion trends is absurd. Kate Middleton doesn't do catwalks; however, she does wear designer clothes from some of the greatest designers in the world. Modern fashion is simply a new era in the long history of fashion. Think of the corsets, wigs and white tights of the 19th Century.
To answer your question: The differences in lipstick across the evolution of Chinese history are evidence of the changes in thought and trade in each dynasty. For example, in the Wei Dynasty, with increasing influence of Buddhism from India, people were generally obsessed with "becoming gods and goddesses" and dressed accordingly. Therefore, the lips of many Wei women, as you can see on the website, are slender and long, like you can see on many Buddha statues from that time period.
Another example: during the Tang Dynasty, with increased openness because of increased global trade, women were given more rights and the fashion trend for women was being slightly heavier, which coincides with the increased accentuation of the lip.
There are a couple of sources you could refer to; however, they usually call for some knowledge in reading and understanding Chinese.
If you want a definitive guide to most of Chinese culture and artifacts, I would recommend a YouTube channel called 马未都讲历史. This is a channel owned by one of the most prestigious historians in China and analyzes the ideas behind much of Chinese culture. He speaks in Chinese, but I am sure that there are English subtitles.
These are two pretty good resources I found online by Stone Brooks and Cambridge University respectively
They explain how cultural, economical and political factors all affected the different styles of clothing throughout Chinese history.