I mean, isn't this weapon hitting everyone nowdays? I was spared until now for some reason. Maybe not looking good at all is finally paying off, but I digress.
First of all, shit are you really approaching the end of Book One? How long have I been asleep? Did I lose anything? Did the Old Ones finally take over my brain? Anyway... I like the approach of making the "Gender Canon" thing. Especially by making it that whatever each individual player is doing in their game or whatever name or gender they chose is set in entirely alternate realities, because that's not something often done even by big names in gaming. For an example, to this day more than 10 years after it's release, it was never set in stone who the Dragonborn is. Was he a man? Was he a Nord? Maybe he was a female dark elf?
Of course there will be people who proudly hold sticks up their own assholes regarding things they understand very little about wanting to jump on your throat for this, but you made it clear that it won't invalidate their in-game stories and choices. If they decide to whine about it, it's not your problem. After all even in the AVN community there are many developers currently playing with the idea of alternate reality/multi-dimensional stories.
All in all, I 100% support this idea. Now if you'll excuse me I'll find myself an Elder Sign to ward off whatever tricks the Old Ones are playing on me and get back to Mythos.