> The they/them swap is the most elegant implementation I am aware of.
Far from it, it only creates confusion and injects ideologically charged "pronoun language" into the discussion. If you feel the need to make clear that yes, the person you're talking about can be a man as well as a woman - something which most people realise and the ones who don't won't anyway no matter which words you use - use something like s/he or "he or she". The first form is just as short, is not ideologically charged and does not create ambiguity.
Prefer harmless confusion to harmful intolerance
Unless they are non-binary? But in some languages you'll still run into trouble. In Italian, if your masculine, it's non-binario, and if you're feminine, it's non-binaria.
What confusion does it create?
You may genuinely not know the gender of an online nickname, and, frankly, you also don't really have to know? Why share this metadata in the first place.
I kinda see your point regarding "it pulls in culture war", but, to be fair, it's "they/them". Language that - in this very usage - predates the culture war by centuries.
So.. idk I think you might be wrong here.