The parent lists a handful of European startups. Just incase that list was being presented as an example of Europe's startup prowess, I just wanted to temper any enthusiasm by pointing out that on a per-capita basis, the density of startups is much lower in Europe.

The attempts of the EU try to make Europe something like a country ("United States of Europe") and yes, Europe is much more segmented (yet alone by languages​, but also culturally). We all know the problems (a money union without a full political union and Brussel dictating to formally self-determined states/countries). You are twisting reality

According to wikipedia, in 2015, the population of Europe minus Turkey and Russia was 628 million, while the population of US was 321.5 million. That's about twice the US, without even addressing the debate about whether Russia and Turkey should be included.