> This is part of the reason why American tech companies are so successful though.

Nothing to do with biggest economy in the world for sure.

That helps, but there's a reason why the collective economy of the EU has produced only like 1/10 the number of unicorns over the past 30 years despite their GDP being around 2/3 the US's

Almost like producing unicorns is not the single most important thing in the world.

Well with respect to economic dynamism it ranks pretty highly.