I think I agree with where you're going, but it doesn't seem like a huge paradox to me. As I understand it, it may be that all else being equal, a better social safety net (such as healthcare available outside of a corporate group plan) encourages more entrepreneurship, but all else isn't really equal: we don't have a version of the USA that is mostly the same except that it has a national healthcare system. Instead, we have countries that differ on dozens of axes, ranging from governmental policy to culture to physical land to history to language, and are trying to assign blame/credit to each of those axes. You could even do that within the USA: why are there no big tech companies out of Alabama or Ohio, despite their governmental systems being generally American-style?

I do agree that the American healthcare situation is a major problem, speaking as an American expat in Denmark who hopes to move back to the US someday, and sees healthcare as one of the major barriers. I'm cautiously hopeful that PPACA will solve the worst of the problems, enabling me to buy individual health insurance. But I think it's hard to prove that either way based on cross-country comparisons.