>>716123109 (OP)I actually did a study on this about six or so years ago when I realized it was much more common to see Australians in online video games than Texans despite Texas having around 6 million more people living in it.
At its core, the higher your population, the more likely you are to be able to draft a better team in sports or video games or anything competitive. It's just basic statistics--having more people gives you a higher chance of finding players with natural talent and top tier players in a given population will be more talented than vs a smaller group. Europe as a whole has a higher population overall than the US and that alone means there's a higher chance of finding skilled players there. (Note that this is true for China as well).
But narrowing it down further, it's not just total population which can skew the favor but also the part of that population that plays games. Taking various studies over the years, Europe's gaming population is anywhere from twice to three times as great as the US depending on the game in question. Europe has a far larger pool to draw from than the US when recruiting talent, and worldwide leaderboards usually reflect that with a few outliers in particular games.
Going back to my first reason for looking into the question of why I see so few Texan players comparatively to similar sized locales, it seems that there's quite a few people within the population of the state that simply do not play games, or at least do not play certain more involved games compared to the rest of the world. Going back to Australia, a lot of the population in AUS is white or asian and lives in urban population centers, which represents the primary demographic of people who play games. In Texas, over half the population is non-white and whites predominantly live in rural areas which have much lower rates of gamers compared to their urbanite peers. Basically, the actual population of gamers in the US to EU is very low for these reasons.