Honestly, you have to be pretty ignorant to hold this opinion.
Even if you account for the 'unicorn' adge there is barely have innovation in Europe. On the social front too too, European pay and ownership is more concentrated in the hands of the leaders and is less evenly distributed than American counterparts.
Your comment strikes me a bit as if it comes from a defensive point of view instead of taking a hard look at things.
I would be very surprised if this was the case. Could you please back this statement with data?
Remove California and New York from the US list and ...
Europeans should worry more about building quality companies and broadening their tax base instead of getting salty about the money saved from foreigners.