If it easier for a US firm to move into European markets than it is for Europeans to? That is 100% on the Europeans. The difference between 70 million and 300 million in the home country doesn't make that much of a difference of how easy it is to break in to the German market - the problem is that French regulators would never allow a French Google to grow.
If France had a Google-like company, it'd end up like Nokia. Hiding at number 16 on a list somewhere, rather unremarkable, trying not to think about what could have been.