Hot take: the problems here are cultural.
Consider these data points:
1. The US is a country of migrants (ignoring the blight of slavery for now), whether those be those seeking a better life from Europe originally, later China and later still Central and South America. These are all people who uprooted whatever lives they had and legally or illegally migrated to the US. IMHO you still see echoes of this "pioneering" culture and I think it's no accident that the peak of the frontier, the Wild West, and homesteading in general have been deeply mythologized.
But look at TV shows like Gold Rush or Deadliest Catch. Whatever creative license is taken here, you still have people who will take the risk of working a dangerous and dirty job for a share of the proceeds.
The average American just seems to have more of an appetite for risk than at least anywhere I've been in Europe.
2. The much-discussed "Protestant work ethic". As exploitative as it is (and it is exploitative), the willingness of Americans to work all the time has an effect that I don't think you can dismiss.
3. Being comfortable makes you more risk-averse, even lazy. We all joke on here about Europe with its 6-8 weeks of vacation, 35 hour work weeks, universal health care and a year of maternity of leave to some extent. These are all good things. The upside of not having those things, if there is one, is that (IMHO) people have a greater motivation. Again, I'm not saying this is a good thing. It just... is.
4. 330M people most of whom speak one language (English obviously). You can't argue that this doesn't make things easier.
5. The barrier to education that is cost with a legacy admissions system led to the endowment system that created venture capital.
For the record, I'm Australian not American and the above isn't intended to extol the virtues of American culture. For example, the fact that a near-majority of the US thinks it's acceptable that a trip to the ER can bankrupt a significant portion of the population is cruel, even reprehensible.
EDIT: corrected less risk-averse to more risk-averse.