It depends. There are two populations, true "Americans" born in the country... and everyone else. The true Americans do not want to leave. If they do, it is about pay/taxes and if you ask them they will generally expect to come back to America eventually. The US remains very competitive for retaining such people.

But for bringing elite minds from outside the country? Heck no. Sure, for the right price they will come, but few want to bring their families to actually stay. Ask someone like a surgeon or physicist whether they want to work in the US or Canada/UK. They will say something like "ya, to make bank for a few years, but long-term I would rather live in Toronto than New York, Vancouver rather than Seattle." The perception of the US by people outside the US is not something America pays much attention to these days. It is suffering.