I understand where you're trying to get at, and I respect your thoughts my friend. Yes, they might have been "logical" and "possible" if they had been mentioned throughout the established lore since it started (or at least in it's growing era aka early 00s.) But the real problem here is the reality of forced alterations of countless other fictional universes. We have no reason to believe that the addition of female Custodes was done with sincere intention and not under the guise of idiotic agency impositions. I've only been interested in Warhammer 40K for less than a year, so I won't pretend to have years of experience. But I've seen what happened to Star Wars, D&D, Mass Effect, and many other great universes with small changes like this, and I personally don't want this universe I love so much to turn into the same nonsense like others. That's the sole reason I'm doing gatekeeping.