Not to mention the difficulties in even determining what the 'market' is. For example, if they are looking at that market of photographers who typically work for wire services, then it could look artificially skewed towards a male demographic - not because there aren't women doing that kind of work, but because they are not being given those assignments nearly as often as men are. If as many women who wanted assignments actually got those assignments more regularly and consistently (like the men are accustomed to getting), their market representation could be a lot higher than the 15% mentioned in the article.
What are you talking about?
1) What assignments are female photojournalist not getting?
2) How many women "actually" want assignments that the men are "regularly and consistently "getting?
What I was in school majoring in Communications (journalism), granted it was decades ago, but men far outnumbered women in that major. I cannot remember any females studying to be a photojournalist. Just based on sheer numbers of qualified journalists, females would be underrepresented when compared to the general population. Having worked for newspapers and wire service, what few females photogs we had on staff, (when I was at the Times we had about 16 staff photographers with one female inclusive), was assigned the same stuff the men got. She was not discriminated in any way on any assignment. The only exception I did see was when she was assigned to shoot the Academy Awards. The men were provided a Tux Rental allowance and there was no allowance for gowns. She protested, along with the most of the staff, and she was ultimately provided with the same Tux Rental Allowance as the men. So, she rented a tux and wore a man's tux to the event. She shot sports, breaking news, fires, features, et al, no different than the men. (She did look better in her tuxedo than we did in ours.)
In war zones, the percentage of women to men was significantly less than Stateside work. Reporting a war zone zone is volunteer work. Back then, females war correspondents were few and far between. Again, no discrimination as I could see and experienced. I've seen women neck high in the same $**t I was neck high in.
The 32 photographers per Nikon's Web Site:
"Meet 32 creative individuals from Asia, Middle East and Africa, and join them as they embark on an experience with the latest FX-format D850 in their respective genres of wedding, nature, commercial and sports. With their expertise in photography and videography, the D850’s technology, and Nikon’s craftsmanship, this is one DSLR ready to set a new world of limitless creative imaging possibilities."
In summary, Nikon was wrong and guilty of discrimination, by general US standards. (I can only speak of US standards, while I am sure other countries share similar equality standards.) I am confident there are plenty of exceptional women photogs shooting "wedding", "nature", "commercial" and "sports" in Asia, Middle East and Africa that Nikon could have called upon in the name of fair play and equality.
Interestingly enough, Nikon's highlighted 32 male photographers from "Asia, Middle East and Africa", yet Nikon included four photographers from Australia which is not part of Asia, Middle East or Africa.