A discriminatory bias cannot be measured by simple proportions, like how many women work at Company X out of the total, and therefore it cannot be eliminated by something naive like a hiring quota or similar. Such a program necessarily involves making decisions based on gender, and so on and so doesn't avoid being bad.
The concept of "workforce diversity" is basically rooted in poor understanding of statistics, together with a willingness to apply a corrective discrimination. Even if half the software developers in a country are women, and there is no bias anywhere, it can still so happen that men constitute, say, 80% of the developers in some organization. Such an event has a certain nonzero probability which allows it to happen.