Not just government research being lopped off, but in universities and corporations too. So them wanting to leave is understandable.
And even after this all comes to pass, whenever that will be, there's always the risk of an emulator doing the same after getting elected. So it's not like, let's wait some years and things will be back like they used to be.
Doctors have been leaving states where abortion and other related procedures have become illegal. Students are choosing to not attend medical schools in those states as well. And this is medicine in general, because who knows how wide whatever prohibitions might be in the future.
So now not only do we have a brain drain in those states, we're experiencing it all over the United States now. And given that a lot of doctors and scientists are foreign born, with the threats they're experiencing in colleges now, well, there goes that source. It's not exactly like Trump's favorite poorly educated are simply going to decide to go work on PhDs to make up for the deficit of foreigners. The United States of America is transforming into a Third World country overnight.