Our system has hundreds of headmates. Out of these, not a single one seems to actively identify as a strictly binary person. We do have headmates who identify as being a binary gender, but it's always part of a genderfluid, multigender, genderqueer, and/or gender ambiguous experience.
Growing up, we were raised a girl, but we never really had a strong sense of gender either way. There were things we liked about being a girl, but also things we liked about being a boy. If you had asked us what gender we were and told us we could be any gender we wanted to be, we'd probably say we were both a boy AND a girl, since that was our best concept of "gender that isn't strictly male or female".
While we'd say that the child version of ourselves - the person Blue was at the time - might be ambonec or androgyne, the collective self the system considers themself to be is not. The collective self is more so an agender masculine person, albeit with caveats like "genderfluid" and "genderflux" and "demiguy".
We now understand we were likely intersex and raised with headmates who were intentionally given odd concepts about their genders, so that might explain why binary gender never made sense to us and why transitioning to being binary-leaning feels like a transition to binary, not just a transition to male.
However, even though our gender changes and does relate to a binary gender, we never consider ourselves fully represented by the concept of the gender binary. Therefore, we are collectively genderqueer.