I think a missing piece of this is that Iceland has a different political system than us - proportional representation. Studies of shown countries with proportional representation outperform their peers due to a greater emphasis on the wellbeing of the economy as a whole rather than geographically concentrated industries, and through a greater openness to trade. The gap is about 1% of growth per year on average, which really adds up over a long period of time.

Knutsen (2011)researchgate.net/public…

Afano & Baraldi (2015) degruyterbrill.com/docu…

Evans (2009) onlinelibrary.wiley.com…