I think the point is that the author of the piece has also constructed sentences wherein the ambiguity can be argued away. That doesn't make it more useful, tho

I think the point is that the author of the piece has also constructed sentences wherein the ambiguity can be argued away. That doesn't make it more useful, though. Replacing "he" and "she" with "they" both removes information and introduces an ambiguity in number. downvoter: am I wrong?