Because there is less competition for jobs and grants. Europe spends more on academic research (as a fraction of GDP) than the US, but there are more people competing for the funding.
The more important US vs Europe difference is that in US there's much more funds for the research -> startup -> scaleup stages.
There's plenty of academics doing fundamental research in Europe. But somehow the ball is dropped on turning that research into successful businesses. So eg. uni graduates doing research in EU, then move to US & found a startup there, is sadly a common pattern.
As I understand it, mostly due to funding suppliers (gov, VCs, banks etc) being more risk-averse than in US. Regulation pressure doesn't help either.
The attribution here is that the researcher works for an academic institution. It reflects the reality that the US funds much more research outside of academic institutions than Europe.
Are you sure about that? Most people miss the fact that a sizeable % of our military budget is slated for research grants/funding.
I'm a physicist in academia, and the amount of money we have gotten from DoD branches for things that have no immediate military applications is like 40-60% of our budget YoY. Like for straight fundamental physics research.
Most scientists I know who have gone to Europe have had to go into the private sector. And the famous ones I work with have gotten like blank check $10M offers from max planck and directorships with guaranteed $1m/yr funding, and still turned them down.