I think one of the reasons, other than legislation, is lack of motivation; it is more or less egalitarian and that promotes mediocrity, not innovation. In US you can become filthy rich relatively fast, not in Europe, so why bother? Just see the IT salaries in Europe vs. Silicon Valley, they are a lot lower, so really good and ambitious people move to SV, don't spend time in Europe.
because money is the only prime motivator in life?
Also, this egalitarianism and promoting of mediocracy you speak of makes no sense in regards to people who want to attain personal growth. Not to mention having a system like the US comes at a massive cost in regards to the wellbeing and welfare of the general population.
Innovating isn't just about money. Not to mention a ton of innovators exists in the EU, they are just not the same scale as amazon/google etc.
I never said money is the only motivator; also egalitarianism and promoting mediocracy does negatively impact people who want to attain personal growth, being treated the same as the village idiot is not a morale booster. Appreciation is a top motivator according to Maslow.