Yeah, I really don't like that, I've never seen why being female would require a whole different set of enhancements.
It's not that I dislike the Adeptus Soritas, it's that I just don't see them as a counterpart of the Astartes (to me they're more like hyper elite stormtroopers+faith). Heck, I got into 40k back during the days where the Sisters were out of focus in favour of the Imperial Guard (which is, and always will be, their only name, no 'star military' here), so about the end of Forth beginning of Fifth, and left the wargame once the Focus had shifted so far towards Space Marines you got powered armour inside a bigger suit of powered armour and the Sisters of Battle not getting a proper codex when the Blood Angels did.
Might start up a new army of Guardsmen when I have the space and money, although I'm considering just moving to 15mm minis.
I mean, I get that, but to me saying 'all Space Marines are male, but some of them identify as women' is saying two statements that cannot be true at the same time. Plus as I said, the idea that they are intentionally indoctrinated to be male because the Emperor was sexist and having this filter down over the succeeding years to me fits with the Grim Dark nature.And as far as the other explanation go, I don't really find it objectionable. The requirement that the individual be AMAB because they're working with the stunted Y-chromosome is pretty reasonable to me. Requiring the individuals identify as male is well, sexist and kind of offensive.
Like, my views on gender mean I feel strongly that somebody who identifies as a woman is female, no matter what their body looks like, how long they've spent living as their gender, or any hormones they are taking. A Space Marine who truly, deeply identified as a woman to me would just not be male (even if they might be 'biologically male).
Then again, I also don't have space marines appear in games. Not even as PCs. If they're on the same planet they're not at the same bit as the PCs are and they're dealing with a more military threat anyway. If I do need a 'highly trained military' NPC I'll go for either a stormtrooper or a SoB depending on how much I want to play up the religious aspects of the setting. I'm generally working at too low a level for Space Marines to care anyway, with PCs doing the grunt work in dealing with corruption both mundane and Warp-influenced (I very quickly settled on 'Ordo Herectus Acolytes' back in the days of Dark Heresy), or if I ever do run a Rogue Trader or Ascension level game the PC wills be dealing with stuff Space Marines aren't supposed to get involved in.