Several prominent Chinese figures, including top Harvard mathematician Liu Jun, award-winning computer scientist and blockchain expert Chen Jing and rising AI star Fu Tianfan, have since left the US and returned to China to take up roles in prestigious institutions in cities like Beijing, Nanjing and Shenzhen.
i wouldnt call it reverse brain drain, the problem with china is having the CCP as the govt, which they can disallow any type of research they dont like. also china has a problem innovation, instead going for reverse engineering through industrial espionage which is much easier to do then performing hypothetical research. the most useful research they done is mostly around botany/discovery, dinosaurs, because plants have a massive biodeversity in china