You certainly put a lot of time and effort into being wrong. Any first year undergraduate writing course will tell you that to make an argument you need to address the counter-arguments, which you have failed even to mention. Diversity of contributors isn't a social justice goal, or even a cultural engineering goal. It is aimed squarely at increasing the diversity and caliber of content. Not only does the small proportion of women mean that millions of them with huge amounts of expertise to contribute are unheard, it also means that their perspective and approach are underrepresented or missing entirely.
And yes, the same is true for others - not only African-Americans, but Africans. Not only people of "Indo-Asian" descent, but the people of the Indian subcontinent itself. This is not an American movement, yet the "global south" is deeply under-represented, and the WMF has been working for years to address this issue. This is, again, because diversity of contributors matters for the breadth and depth of coverage in our projects. The goal of the Wikimedia movement is the sum of all human knowledge, not the sum of knowledge held by white men between 15 and 35 living in Europe and North America.