Good chiefs of staff discourage that kind of talk.
But yes, in the larger sense, generals have spent their entire careers in a male-dominated workplace. There aren't many women three and four star generals because an important part of getting to that level is distinguished combat experience, which until quite recently wasn't available to women.
And Kelly was a Marine. I haven't looked for statistics, but I'd guess there're fewer women in the Marines than in other branches of the military.