I see you didn't read what you linked. "The OECD data are not measuring the movement of non‐Chinese into China or non‐Americans into the United States. The OECD tracks inflows and outflows of published scientific researchers based on changes in institutional affiliation."
So immigrants are weakling, despite disproportionately working in some of the most grueling industries. Do you really think far labor, for example, is full of weaklings?
This "study" has been repeatedly debunked by researchers of all ideological stripes at this point.
-It's including $5 billion in expenses for US citizens
-FAIR's population estimate for illegal immigrants is comically bad. It's literally impossible given we know migrant outflows from several countries
-Sales tax estimate is awful and translates to each illegal immigrant paying only $323 each year. That implies that each illegal immigrant is spending way less than 10K a year, which is laughable.