The jury is still very much out on whether "Turnabout Intruder" said anything about women not being able to become starship skippers; whether the writer of the episode intended any such interpretation; and whether it is even possible to interpret the episode that way. Certainly there was no suggestion that Janice Lester would have wanted to become a starship skipper, so it's quite convoluted to think that the line would refer to the putative obstacles to such a desire.
(This in no way suggests that Janice Lester would have been a progressively portrayed character or anything, of course. But as said, the central element of this episode was that she was crazy. The story wouldn't have gotten any better with a more progressive set of legs.)
In turn, while the description of McGivers may have been conservative rather than progressive in the 1960s, insisting that it still remains conservative is, uh, rather conservative. McGivers was the ultimate Mary Sue: she wrapped two dominating men around her little finger, got to do a little hurt/comfort and rescue fantasy stuff with both in turn, and got exactly what she wanted in the end. This is HBO stuff from today's viewpoint...
Eventually, McGivers got to be the First Lady of an entire planet. If we don't accept T'Pau as the Space Pope, then McGivers is actually our highest-ranking female character!