Take Geoffrey Hinton and his students, for one example. Moved from the USA to Canada in the Regan era. Hinton (and Canada in general) saw an influx of otherwise USA-bound students from 2016 on. And it's just happening again.
I was a PhD student in deep learning ("AI") in the US from 2018 through 2022. The "Muslim ban" at the time saw so many students who had their eyes set on the United States look elsewhere. During the 2020 election cycle, a fellow PhD student of mine (I was the only English student in an all-Chinese lab) thought Trump would win the election, and expressed that as, "I am so so so so so sad". (Anyone who has tried expressing their feelings in a language new to them will recognize this pattern of using intensifiers like this.)
But the Project 2025 changes we saw were unique. In my perspective as a former academic, I don't think people outside academia generally appreciate the extent to which the reputation the United States had for research has been damaged.