The Poppet Sisters

The major mechanic of the entire franchise is the ability to disguise yourself with uniforms found throughout the level. This allows you to access areas of the game you wouldn't be able to otherwise, with other NPCs in uniform controlling your access to areas.

Now, because Agent 47 is Male, that means that every NPC whose clothes you can steal, and therefore every NPC that poses any mechanical threat... must also be Male, no exceptions.

This means women cannot serve a mechanical purpose outside of being a civilian witness or a target. They cannot be construction workers, police offices, chefs, or any of the innumerable NPCs that you can disguise as. Women are systematically not allowed to be important because their build is incompatible with 47's. (it is worth noting that important/non-target NPCs are also not allowed to be fat, disabled, or small for this exact reason).