DISCLAIMER: Not saying that every player / Game Master needs to be concerned with this. It *is* a private game between you and your friends, after all. If you're all happy then go with it ... whether that's an all-woman universe, all-man universe, all non-binary-gender-universe or anything in between. It's a game. Enjoy it.
Anyway for those who want more female representation at their game table but are struggling with it...
I don't know how most people are but I know that I'm somewhat sensitive to issues of gender diversity in campaigns I'm in. This isn't to say that I keep a running score of male versus female NPCs (well, not always) but I do notice if the ratio skews quite far toward one direction. As a woman, I notice the ratio more when it involves women than other categories though I am beginning to pay attention in the other areas as well.
For now, though, let's talk about female NPCs as I can't speak for the other groups though I imagine they may feel similarly.
I know that some Storytellers aren't comfortable roleplaying female characters. I get that. I don't think Storytellers are somehow 'bad' when they don't roleplay them. In that case it'd be fine if they at least threw in enough important background females to feel like my character hasn't suddenly woken up in an alternate universe where everyone is born with a wang. At least have that random news anchor reading out that random document, the president who is never met but occasionally referred to, or the taxi driver who is briefly described be female.
Sometimes it's not even the Storyteller's fault but the other players. I've seen other players make comments like: "My, my, what hairy legs you have, m'lady," when a male Storyteller was playing a female character. If you have immature players like that then I'm truly sorry.
I also understand that in some campaigns, everyone will be a male. If I'm in a campaign set in a WW2 submarine, I'm quite happy to play a male PC surrounded by male PCs in a hierarchy full of men. That's absolutely fine. I wouldn't even notice the absence.
But when a vampire court is full of male characters with a single Daeva femme fatale among them? That gets annoying because there's no canonical nor real world reasons for that to be so.
You might ask why it matters.
Well, it's an issue of representation. Humans are innately social creatures and we feel this discordant internal *twang* when there's no one else like us in that situation. It makes us feel, inadvertently or not, a bit like an intruder. That's not a fun place to be as a player. It makes me feel like my options are limited. I get that enough in movies, television shows and books. I mean, it's getting better. When I grew up Alex Mack, Buffy and Xena were basically it.
Does this mean you're a bad person if you haven't been including female characters at all let alone strong ones?
No. I've had a fantastic Storyteller who identifies as a feminist run a game for me where over the first few sessions I met 10 NPCs. 1 was female. That one also happened to be a brothel owner.
Since this was a solo game, I brought it up with the Storyteller. On several occasions. Repeating how much it affected me and asking for him to include more women. It always was somewhat of a problem though never more obviously than with that particular campaign.
To begin with, he didn't believe it. Then when I started rattling off names and ratios, he felt bad. He thought that it shouldn't have been a problem for him. He should be able to simply include plenty of strong female characters. He believed they exist. So why wasn't it happening?
In his case, it was simple. His whole method of generating NPCs was to pick up archetypes on the fly and then develop them as a character and add multiple layers of complexity until they became like real people. This actually did help in certain areas of diversity - such as sexuality - which isn't the first thing you notice about a person.
But in the case of gender, his particular technique failed him. There's a huge variety of male character skeletons out there which you can grab as a Storyteller and dress up at your leisure but far fewer female ones. So when he reached for an image of a 'truck driver', 'scientist', 'thug', 'dodgy businessperson', 'evil CEO', etc. he found male ones and he included them. Even when he desperately wanted to include more women, it just didn't happen until he started to actively think about it. Mostly he just grabs the archetypes and then makes it female these days and that works for me as his characters are all uniquely individual.
Later some of those easy-to-reach ideas will be female as the rest of the creative universe starts exploring those ideas. In the meantime, though, it will likely require conscious effort to include a more diverse representation. It was easier for me because I am, naturally, more aware of it but even I have to actively work to create a more sensible male-female ratio.
Your ratio needn't be the same as mine. Your ratio might not need to change at all. But do consider if the ratio you end up with is what you and your players are actually after.