Seems to me there’s a lot of preciousness, combined with the usual media hype, about extreme minorities' or individuals' situations having been excluded from the questions.
This is statistics, gathering percentages.
Take the gender question for instance. The intent is no doubt to get an understanding of the male/female ratio in the various parts of NZ. I’d hazard a guess that more than 99.5% of those who completed the forms would have ticked either male or female. Obviously then the 0.5% who left it blank identify themselves as neither or as something else. Statistically irrelevant. (I can’t recall if it was possible to leave it blank. Even if it wasn’t and people abandoned the form in protest those numbers would still be statistically irrelevant.)