It's horrible to reduce these things to labour market conditions but I suspect science will continue to be done. Maybe not as expected, but it won't grind to a halt.
Historical comparisons to 1930s Germany and lysenkoism would be interesting. There was a brain drain. Ignoring the politics, there was a hit to the intensity of work in some fields. Soviet genetics took a huge blow. Rhodes suggests German chemistry and physics suffered.
If design and IPR behind things like mRNA drugs shifts, to europe and asia will that necessarily be worse for the world overall?
The big thing the USA has going for it, is acceptance of business failure as a norm. A million IPOs start and ten succeed is seen as a victory, in Europe the 999,990 failures are painted as the cost-to-much outcome.