The most recent 60-Second Science podcast discusses the abilities of men and women in playing chess. One can argue that men are better than women at playing chess because all world champions have been men. However, that only suggests that the best men are better than the best women. It is possible that the distribution of chess ability is identical for men and women. Since more men than women play chess, the best men are the best of a larger population.
I looked at this exact issue in an earlier post on Olympic performance. That posts asks what to expect if men and women had equal ability in a sport that more men chose to compete in. The same considerations apply to country sizes. If two countries have equal ability at a sport, the larger country is likely to field a better team. The best performers from a larger group are typically better than the best performers from a smaller group. This post looks at how to quantify this observation using order statistics.
The podcast mentioned above says that the difference in male and female championship performance “can be almost entirely explained by statistics.” I assume this means that an order statistic model with identical distributions fits the data well.