What is US losing, relative to Europe/other countries?

I can't really think of many notable things to come out of Europe as of late... besides maybe covid vaccines but its hard to really say that when 90% of the wikipedia page for the "creators" is about research and contributions that they did (and could really only do) in the US.

You allude to it yourself in your example. People, from all over the world, were doing research in the US, because that’s the only place they could really do it. Now that this option is disappearing, the system will have to adjust and find another place. When that happens, US loses. Until it does, we all do.

People have been claiming "this is the end" of the US, for some reason or another, ever since I've been on the internet (since 2005).

This same sentiment was going around in 2016 when Trump was doing those ridiculous "bans" on immigration. Since then I would argue the US has only increased its influence and power over Europe. Europe needs help with the war and the US has already given immeasurable resources. Europe has almost no skin in the game when it comes to AI. Maybe that's a bubble but the point still stands.

Ofc I don't agree with what the current president is doing, but the idea that businesses and research will flock to Europe is amusing. They've certainly introduced enough barriers to ensure that won't happen.

Just to make it clear, I never said the next place will be Europe. Could be anywhere. Systems evolve creatively, I would not dare a prediction.