Number one economy yes, but other measures lag: education, health care outcomes, overall happiness, life expectancy...
I suspect that when you bring a competitive attitude into every aspect of life it limits how much you're willing to invest in systems that don't seem to give you an individual advantage. Americans are much more against single payer healthcare, or investing in public transit, or other forms of social support than their peer (or "near-peer", to use the government's preferred term) nations.
It almost feels like a comedic extrapolation of the classic sports-team movie arc: Sure, it's possible to create a team that prizes winning above all else, but is winning all that's worthwhile at the end of the day?