Well, anecdotally, the reason my mom ended up as a programmer is because she had an admission/scholarship to study engineering in college revoked because she was a woman - they didn't technically exclude women, but they told her they already had one in the department and didn't need any more. So she got a degree in math (this was before computer science was a thing) and ended up working for engineers, taking their problems and turning them into code.

Now I can't say how common this was without statistics, but you can see it paints a picture of how discrimination in one area could potentially affect another in a systematic way.

It could well be (and I'm sure I'm not the first to suggest it) that reduced discrimination in areas that require both technical and soft skills have caused an exodus of women from mere coding, because it's both more lucrative and enjoyable for many of them.