Well the author of the article is no longer a New York fashion editor and I'm going to presume that likely she lost her job in print media as fashion and beauty magazines have downsized or closed as advertising has moved to a digital and social media platform. So her lifestyle has changed and she no longer has to wear high fashion and she's also moved to an area or job where she does not have to be dressed up, thus the yoga wear and a more casual lifestyle. It's understandable that she seems to be mourning her old lifestyle but her schooling and job don't require her to be dressed up. Maybe she would feel out of place if she did get all dressed up like she did when she lived in NYC.
The irony too is that in the article she mentions the Lululemon founder Chip Wilson and his wife Shannon as they are not particularly involved in that company now but they have certainly made a lot of money selling overpriced yoga wear. They own one of the most expensive homes in Vancouver, B.C. Canada, it probably worth at least $50 million dollars. And that store doesn't carry clothes bigger than a missy size 12 either. For whatever reason people really like Lululemon, but anyone not in that size range will have to shop elsewhere for yoga and athleisure clothes.