According to [1] 14.5% of all EU workers are self-employed (i.e.: they have their own business, as small as it may be) whereas only 6.6% are in the USA.
Entrepreneurs start companies that are meant to grow beyond themselves and aren't just a legal framework to provide their work.
Not to disparage anyone who's self-employed. I am too, but I wouldn't consider me an entrepreneur. I might become one, but that would mean changing my work setup.
I am fine with not every useless thing to exist and waste resources on that.
What the EU lacks is the Ivy->Startup pipeline and insider/investor networks with access to old and old-ish money. And also the relentlessly aggressive branding and self-promotion (and tolerance of scamming and grifting) that defines US hustle culture.
If you're not in or around those networks already your chances of success in the US are pretty slim.
https://www.brookings.edu/wp-content/uploads/2016/07/02_econ...
America is a great place to be rich. In Europe they tax you. But why should a millionaire care about healthcare for the poor or homeless shelters?
Anecdotally, I live in Europe and know plenty of entrepreneurs, albeit mostly either in the tech space or as incorporated side gigs.
Source: https://www.nationmaster.com/country-info/stats/Economy/Micr...