I think often the RPGs can be better at the Satirical angle than the central wargame. Dark Heresy does encourage DMs to explore the themes — although the mechanics are a bit all over the place as far as supporting that goes.
Necromunda seems to be the one sub-property that actually tries to execute on the satire regularly and with any success, although it's not particularly focused. Don't know why, but I suspect having more Dredd\2000AD in its memetics helps.
Eh, in my experience the people arguing for female space marines tend to be the types that think that the Imperium is emphatically the good guys, they literally want diverse oppressors because they think that when women do it, it's not oppression.
That has not been my experience at all. The key difference between FSM and "More lady drone pilots flying rainbow drones!" is that one of these.is a game that we want everyone to play. We do unironically want more ladies to feel comfortable playing the oppressors because it's a game and the space should feel inviting to people generally.
Other miniatures games (Infinity etc) have near-parity in male and female sculpts and don't have massively more female players playing them. Female warhammer players generally don't feel comfortable with the militarized aesthetic of Space Marines, regardless of whether the person inside the power armor is a woman or not. To make them more comfortable in the hobby, focus more on Tyranids, Eldar, and demons.
The majority of the FSM crowd is men uncomfortable with their maleness, however, and that needs to be addressed.