My low-information view is that the Chinese government is an extraordinarily effective communications agency who very clearly understands the role that university students play in transmitting culture, especially when studying abroad, and has very openly worked to help spread their message throughout their diaspora.

Many US universities have a Chinese Student & Scholar Association and it's not like they try to hide that they are arms of the CCP. (Just for a random example https://myinvolvement.org/organization/cssaatualbany - "The Chinese Student and Scholar Association at the University of Albany is joined and organized by the Chinese students and scholars at the University of Albany of their own record. It is a nonprofit organization that is supported and guided by CCP through the Consulate-General of the PRC in New York.")

Mass organization can do incredible things -- a group of people is much more effective than the individuals.