Hello! Another female here, and I agree with your point about "oppression." Just because certain types of people (gender identity, race, nationality, etc.) aren't heavily involved in something doesn't mean there's a problem. It's a big world and there's lots to do in it. However, when it comes to a single website, like itch.io or any other, it's hard to know exactly who is using it and in what way. Not everyone has a gender-specific username (intentionally or not), and many people visit but aren't visible in the community. Also, the user population can depend on the company's marketing strategy, which may slant things quite a bit.
On the plus-side for female involvement, you can't ignore the offline presence of female friends, girlfriends, spouses, team members, and so forth who assist and support the devs who come to the site, but may not have an active account of their own. Whether they advertise it or not, there are plenty of guys who probably couldn't or wouldn't do what they do without us (and possibly vice versa). ;-)
Anyway, nice to meet another lady game dev here. I mostly work in Unity with C# (some 2D, some 3D), and make offline games and game assets, as well. Feel free to reach out anytime.