Well, I've been hip deep in period science fiction since 1954. Hard Way Home, by Richard McKenna (lead story in this month's F&SF) is the first time I've ever seen women CPOs.
That's defining it too narrowly. I'm not talking about the superficial element of a woman being a military officer or not, but the broader trope of the inclusion of a female character in a conventionally male role such as scientist or expedition member, with it usually being justified by her being exceptional for her sex in the same way Number One was -- cool and detached and consciously unfeminine, but ultimately defined by her suppressed romantic interest in a male lead.
In other words, I'm not saying there was
nothing progressive about Number One as a character -- just that it has to be put in perspective, that it's not as revolutionary as it's often hyped to be, because she was really a well-established stock character type that played into the well-established sexist trope that a woman had to act manly and be an exception to her sex in order to function in a conventionally male profession. Her character is progressive in some ways, stereotyped in others. Because social progress is usually incremental rather than revolutionary. It's important to recognize that texture and nuance rather than try to reduce everything to a single value.
Women are almost completely absent from space-based SF of the time, love interest or otherwise.
That's not true. It was a common trope to have at least one female crew member on a rocketship, like Osa Massen in
Rocketship X-M, Naura Hayden in
The Angry Red Planet, Shirley Patterson and Ann Doran in
It! The Terror from Beyond Space, Virginia Huston in
Flight to Mars, etc. Sometimes the female presence was more contrived, like having Debra Paget's character stow away on the rocketship in
From the Earth to the Moon, but it certainly wasn't unheard of for women to be included on spaceship crews, or to be key members of scientific expeditions in monster or disaster movies. (Sometimes more justifiably than others. Mara Corday's character in
The Giant Claw was a mathematician who did the calculations for the expedition, a role often performed by women in the sciences, as seen in the movie
Hidden Figures. The word "computer" was originally a job title for the people, usually women, who did that kind of work until electronic computers rendered them obsolete.)
M:I has one woman character, and she's usually a femme fatale. That's '40s level "progressive."
But the female lead got as much attention and story focus as her male counterparts, was shown to be intelligent, calculating, and cool under pressure, and was often depicted as capable in physical combat. Much of that describes Uhura, but Uhura never got an equal share of attention. It doesn't matter how progressive a female character's job is if she's never allowed to be the focus character in a story, if she's perpetually kept in the background of stories that focus on the male leads. That reduces it to a token advancement.
And again, the point is not to reduce this to some kind of pissing contest, but merely to put
Star Trek in the context of its time and recognize that the claims that it was
uniquely progressive and revolutionary are exaggerated and unfair to many of its contemporaries. It was part of a larger trend toward inclusion and progress, and there were ways it fell short of its professed aspirations.
Giving Star Trek approbation for work it didn't do is a barrier to recognizing what it did do.
Again, the last thing I want to do is reduce anything to such a facile binary. My goal is to add context and perspective, because you have to consider
every aspect of a thing in order to truly understand it.