Be careful with your sources. I think the trend is unmistaken that more Chinese students have been returning to China these days, but the number 97% strikes me as too high. I don't have my own sources, it's more of a perception and anecdotal evidences.
There is a combination of different factors at play here. Certainly the attraction of domestic opportunities being one, but the US restrictions in terms of visa and fields of study are also a factor, as well as the deteriorating environment against Asian/Chinese but particularly against Chinese. My sense is that the real high-end talents or students in hot fields are staying put and finding opportunities in the US, if only for the time being.
Another thing to consider, there have been so many Chinese students coming to the US for studies in the last decade, such that most of these students are no longer considered to be more elite ones, unlike the generations before them. A vast majority of them are here just for the experience simply because their families can afford it. It's more difficult for them to find gainful employment opportunities and/or they don't care as much after graduation. As a result, the percentage of students returning to China after graduation is a lot higher than that of previous generations.
