“Stop discriminating,” by itself frequently doesn't cut it, though. And when it doesn't, playing to the numbers is another tool to use to attempt to reach a just equilibrium. It gives the minority gender a means of establishing networks of power, gaining positions of authority that can shift the culture and reduce the gatekeeping. While it may be true that deliberately aiming for a ratio stands the chance of disenfranchising some qualified people, the existing situation quite possibly does the same but we don't know it. Survivorship bias and default bias make it very difficult to discern whether the existing ratio is appropriately reflective of the population's nature.

I understand the point you're making that ratio targeting seems immune to indications that a different natural ratio exists that differs from the imposed one, but I argue there is sensitivity to negative feedback. If there really is a natural sample ratio that differs materially from that found in the broader population, businesses will eventually be unable to hire according to the ratio. The danger is of course setting up a system that's wholly immune to that possibility and risk coming to lay upon a Procrustean bed. But I think profit motive is sufficient to dampen that risk. Businesses who are simply unable to find and hire qualified candidates who fulfill their target ratio will abandon that ratio by degrees.