As a Chinese person, this is my reaction:
1. Not bothered per se on an individual case basis, as I have no understanding of the connotation of her wearing that dress, and as she's claimed, she has nothing but appreciation for the culture behind it, so I will give her the benefit of the doubt
2. It's also an automatic reaction for me to assume a negative association with such a phenomenon, based on experiences. There is an interesting observation I've made over the years, while I tend to associate negative experiences with what's described in the article, Chinese people who were born and raised and live in China tend to have a more positive association to such things. I was born in China and left early but assume a strong familial tie with the homeland. I think for those of us who live in cultures non-native to our heritage/upbringing, we have made the inference that when such things happen, it's likely associated with ignorance or the worse case scenario racism, in most cases, it's an annoyance. I doubt the girl in the dress understands the political and historical context of the dress, and it's important, as it's not at all a normalised daily wear in China, it's cultural significance has more weight than its functionality, and knowing that would certainly give more credit to her claiming cultural appreciation and perhaps put her off wearing it. Finally, the group photo pose is ... I don't even know where to start
lol I thought they did a martial art stance at first. That might have been a bit much.