1) If computer programming was a meritocracy, we'd only have the best computer programmers in the field.
2) Most computer programmers are white males.
3) Most people are not white males.
4) Ergo, computer programming is not a meritocracy.
I trust most people saw the logical flaw - the author is assuming that the ability to program is currently evenly distributed. This is not the case. Pick 20 people at random, off the street in Palo Alto, put a gun to their head, and tell them they must solve FizzBuzz, in ANY language. FizzBuzz is famously hard, but it's not that hard; you've got a good chance of getting a few solutions.
Now do the same thing in Bangui (capital and largest city of the Central African Republic). Odds are you'll get a lot fewer. Probably none.
This doesn't tell us anything about whether white males are unusually good at programming; it tells us a lot about the availability of computers and programming training in the 179th (out of 187) poorest country in the world.
In other words, the central argument of the blog rests on conflating ability with opportunities. Because a black female from the CAR is every bit as capable of being a good programmer as a white male from Brooklyn, it follows that black females ARE just as good as white males, and since there are more black females than white males in the world, if a tech company has more white males than black females, it is clear proof of racism and sexism. Except no; in the world we actually live in, the number of people who have the skills, background, and experience to work at, e.g., Google is quite small, and (sadly) mostly male and a mix of white and asian. And yes, that is due to racism, but it isn't itself racist.
But the article seems unable to make that last step, and as such it renders the whole thing rather pointless.