IMO Civ VI is considerably better than Civ V for diversity and inclusion, in particular for having more women leaders. But did that result in more female players?
Maybe, maybe not. But why should that be the only point to measure it by? Having more female leaders will also help male players in understanding there is more to the world than men. It's easy to say "But I know there is" but where I live there are mostly female teachers (apart from that men still dominate most industries), and it's not until you start working in such a place as a man that you feel what underrepresentation means. I'm sure if I were a woman I'd love to see more women in games too (hell, I'd love to see more equality regardless anyway).
People often like to talk about inclusion in video games like they are just that: video games. But they are not, and here might come a point that a load of you think is tripe. Games speak to a modern, general public. In a certain way this means these games will always reflect our current society (use of language, importance of depicting this over that, design, etc.), but it will also always need to take care of how it shapes people playing. What we see everyday shapes the way we think, so I'm all for seeing more women in leadership roles in video games, if that means it's easier to include them in real life too (and I think it does.)
Call me crazy, but I think Leaders should be included based on the historical relevance/impact.
You're crazy! Haha, no of course you're not, and your point is entirely understandable, and one I've often made in my life too. I'm sure most of us, if not all of us, have. But there is one point you're missing, or at least not addressing, and that is the definition of "relevance" and "impact". Not including women in media is of huge relevance in history, so one might argue it's relevant to include them now to offset that balance (the same goes for impact).
Then there is the old adage "History is written by the victor". If you were able to go back in time and speak to a Gaul (nevermind language barriers for a second), they might not agree at all with how we are taught about them.
Finally, there is the falsehood that relevance is equal to sheer volume (more people, more relevance). China, economically speaking, is more relevant to all our lives than Belgium. I'm sure that if you talk to some Belgians whether they think the history of Belgium is more relevant to them, or the history of China is, they'd a least be able to make a good case for the former (or both).
Personally, I want diversity as much as possible. I love learning about new cultures, love seeing different gameplay adapatations, and different cultures and backgrounds (no matter how small) just make the game palette more rich. Then there is the simple argument of having all the work done by about 50% of our societies not being mentioned in the history books, which excludes a lot of friends, half of my parents, half of my grandparents, etc. If it means putting some less obvious leaders in the game to rectify this and make everyone feel more included, teach others more about inclusion and recognition, I'm all for it.