The diagram is completely different from what the text says. Specifically, the text says:
"People can be any combination of these."
And yet the Euler diagram[0] shows no intersection between "Hackers" and "Developers", and it's claimed that all "Hackers" and "Developers" must also be "Programmers." When code and comments disagree,
both are probably wrong.
-- Norm Schryer[1]
In short, while there may be elements of truth, I think the whole article is ill-thought through.[0] It's not a Venn diagram, because not all intersections are present: http://en.wikipedia.org/wiki/Euler_diagram