The more important question is: what is the rate of scientists coming in vs going out?
If they are in balance, then it looks a lot less of a problem. It may even be the case that because of the desirability of working in the US for US institutions the US is gaining the best from all around the world and shipping out a more mixed ability set.
"Using new data which tracks US-trained STEM PhDs through 2024, we show that despite foreign nationals comprising nearly 50% of trainees, only 10% leave the US within five years of graduating, and only 25% within 15 years."
That sounds like net benefit for the US. Foreign nationals come, the US sells them (overpriced) education, they do relatively low-paid but high-value PhD research, and then most of them stay and continue to contribute to US research endeavors and the economy. This is such an enviable position, and this administration wants to close the doors? This is the secret sauce. This is what has made america great.
If they are in balance, then it looks a lot less of a problem. It may even be the case that because of the desirability of working in the US for US institutions the US is gaining the best from all around the world and shipping out a more mixed ability set.