That doesn't back up the assertion; it's easily read as "we make sure our training sets reflect the 85% of the world that doesn't live in Europe and North America". Again, 1/4 white people is statistically what you'd expect.
Fuck, this is going to sound fucked up... but just because you have a 1/4 chance of getting a random white person from the globe, they generally tend to clump together. For example, you generally find a shitload of Asian people in Asia, white people in Europe, and African people in Africa, and Indian people in India.
Probably the only chance where you wouldn't expect this are in heavily colonized places like South Africa, Australia, and the Americas.
