> Just as an example Europe had a few years of exporting the best GLP-1 drugs (finally something in which Europe was leader in science), Eli Lily quickly took it over

You make it sound like Europe was not a leader in any area of science until this one thing which they led in for a few years.

> Terrence Tao was a good example of what happens when an exceptionally smart person stops getting funded by an American University: not moving to another country, but got VC money and created a new company

No, he's an example of what can happen when a Fields medalist gets funding cut. 99% of exceptionally smart university mathematicians and scientists will not be able to get VC money.

With the US both cutting research funding and becoming unfriendly to foreign students many future Tao's that would have chosen a US school for grad school will likely look elsewhere.