Why should the vast majority, or even a sizable fraction, of fields not have a gender or race balance even remotely approximating the balance of the general population? Is it not a 'should' but merely 'it's okay if they do'? If the balance was in the other direction and men or white people were being intentionally denied jobs, would that be okay?
Should it be OK for other things to be unbalanced? Should it be OK if 60% of black people can't get houses but only 10% of white people have trouble getting homes? Should it be OK if 90% of asians are turned away from emergency rooms but only 20% of mexicans are?
You can argue that race/gender genetic differences play a role but it's kind of hard to explain away the widespread imbalances here just based off DNA.