No, it's genetic engineering, part of which is a full body neural interface with power armor, allowing it to be.used as if it's not being worn at all. Most accurately, Sisters ae equivalent to stormtroopers with better gear.
Aside from resolution issues, this is an incredibly patriarchal attitude from someone who is, as I recall, not only male but a white male. To me, that kind of tokenism is offensive and opinion driven. I don't like Eldar because I'm an elf, nor do I like SMs because I'm a fascist warrior monk, but poor girls only are drawn to a thing because of their sex organs? If GW made female SMs, suddenly we'd be awash in female gamers because they avoided 40k due to the lack of female SMs? Nonsense.
There's a reason there's so many waves of feminism. To one, an all-female army, especially huper-sexualized, would be getting their own back. To others, it's patronizingly sexidt and diminutive.
It's a game divised by a bunch if Brits in the 80s based on a bunch of scifi tropes. So, mainly dudes and yes, overwhelmingly white. So what? They weren't making a social statement, nor were they trying to portray a happy, integrated society. It's not white privilege anymore than it would be black.privilege if it was designed in Ethiopia instead and the characters were overwhelmingly black. There's a point one is just looking for an excuse to be offended.
On fluff: You have to be compatible with the geneseed for implants, so being the same gender as the.prarch makes sense. In meta terms, it also leaves half the population carrying compatible genes in the breeding pool.
On models: Bare marine heads should look like they have gigantism, not be an identifiably ethnic type. I also think the bare heads are moronic, and don't see the ethnicity of my.marines as relevant in their armor. To provide ethnicities, the demand would be to add what, a half-dozen heads, but they'd need to be every sprue, because making the assault marine asian while the devastator is black while the tactical is white is so biased.. .
This is fine, because here you're not talking about how female gamers just want representation and that's their issue, but rather that you think it's the issue and more female models would fix it. I disagree- I think it's the fascist grimdark wargame attracting a non-representative male:female ratio inherently- but that's a different item entirely.
Well, they're genetically engineered post humans since early puberty, whether they're more than formerly or notionally male is also open to dispute, IMO