Assuming no bias in the choice of the surgeon, each female surgeon will work on the same fraction of complicated cases as their male colleagues, and thus their

Assuming no bias in the choice of the surgeon, each female surgeon will work on the same fraction of complicated cases as their male colleagues, and thus their success ratios are unaffected by the representation of female surgeons. On the other hand, bias in the choice of the surgeon for complicated cases would indeed have the effect you describe. If this article causes people to conclude that female surgeons are better than males, and thus causes people in the future to choose female surgeons, then the complicated cases will be over-represented and thus their success ratio will plummet