The second and third articles, especially, were keen to emphasise how male-dominated surgery is, so I'm surprised they didn't discuss whether any of the difference in outcomes might be down to more intense selection/higher barriers for women (if only to explain why that's not the case).
If only a fifth of surgeons are female (one of the numbers that was mentioned), it would theoretically be possible that while the range of ability and aptitude among potential future surgeons may be the same in women and men, for some mysterious reason the best 10% of the men end up as surgeons, but only the best 2.5% of the women. Which would result in the average female surgeon being of higher potential ability than the average male surgeon.
Obviously things don't ever work as cleanly as that… presumably there are lots of complex and interacting reasons behind the disparity in numbers of male and female surgeons, and lots of factors besides purely ability as a surgeon that affect whether a woman (or a man) goes into the field, but I did wonder whether they might cover it as a potential factor.