Moving away from grammar, though (which we’ve agreed changes, however comfortably) there’s the reality that any confusion that arises is probably minimal. How often does using “he” or “she” on their own eliminate confusion, given that it only reduces the number of possible people being referred to by, at best, half? And the vast majority of people we interact with are cisgender. I’ve probably only directly interacted with three people who aren’t, two of whom explicitly stated what their preferred pronoun is. And, as someone mentioned earlier, often if you simply ask, they have no problem telling you without taking offense.
One of the people I mentioned is my brother’s kid, and they’re not only gender non-conforming, but they changed their name, too. And, sure, it’s an adjustment to refer tho them by the correct gender pronoun and name after 20+ years of using different ones, but it’s a negligible difficulty (and, frankly, we adjust to name changes all the time when female friends, family, or acquaintances get married and change their name). It’s minimal effort for us, and far more difficult for them.