Started thinking about this post again, and how I mentioned that surveys, polls, and such are often unprepared for systems to answer them collectively, and I think this ties into common exorsexism (whether intentional or not): typical, "normal", binary trans people are always thought of first, always the primary audience, in such a way that they and their experiences are prioritized to the detriment of non-binary people who differ from them, who are then erased through the action of not making room for them, or implying that their experiences do not and can not exist. In this case, you could take survey questions about labels as an example; some trans people, particularly those under the genderfluid umbrella, use different labels at different times. However, these survey questions rarely account for this, and only ask for all labels you use with no further consideration, completely erasing the complexity that non-binary and genderfluid people experience. Similar problems arise with other topics, such as asking how you present yourself; non-binary and genderfluid people in particular may present very differently depending on how they are feeling that day, but surveys are usually tailored to one specific idea/stereotype of a binary trans person. These problems are shared by systems trying to take these surveys.
The answer to these problems is, thankfully, simple: adjust your survey questions to account for these experiences, and remember to seek out diverse voices when constructing your survey. Don't just ask what labels someone uses – keep genderfluid people and their testimonies in mind, consider the impact that genderfluidity may have on what labels someone uses, and ask if the labels they use change depending on internal factors like changing gender. This also opens up the opportunity to ask about labels that change due to external factors, like who you are around, which allows for more in-depth study about being out versus being closeted. In this way, we can see that there is so much out there about trans lives to be explored and learned about, but this flattening of trans studies to prioritize specific, binary trans experiences also flattens our understanding of even binary trans people, who may, for example, use different labels to describe themselves when among different crowds, without feeling that they are oversimplifying, minimizing, or otherwise obscuring their "real" identity (as some particular surveys have implied with how they ask for a list of labels). A simple "check all that apply" question about labels without any follow-up erases this complexity, which could be studied to better understand trans lives.
Other areas in which trans surveys could improve to be more inclusive of non-binary people, genderfluid people, systems, and much more include:
The expectation of a singular name
The expectation of a singular, static gender presentation
The expectation of a singular, shared definition and cultural association of femininity, masculinity, being a trans woman/man, and so on; we ask for the understanding that these things are ultimately defined by the individual, and what is feminine to one person may be masculine to another (as just one example)
The expectation of a singular, "default" (usually white and Western), and static cultural context for gendered language, gender roles, etc. (see: multicultural households, trans people of color, etc.)
The expectation that one's relationships with others are static in intensity, attraction, and type (see: waverships, different alters having different relationships with the same people, etc.)
The insistence on using "persons" language for individuals even when the focus is statistics that refer to physical bodies, erasing and dehumanizing systems who consider themselves multiple persons (consider: beings, entities, selves, or just taking the long route to be specific about what you're asking)
Leaving out or not taking into consideration forms of dysphoria that do not have to do with gender, such as species dysphoria or the dysphoria that some intersex people experience related/due to medical intersexism they've faced (described vaguely here to avoid triggering anyone with too much detail; seek out intersex voices on dysphoria for more information), but which may impact one's identity or gender related dysphoria
Leaving out or not taking into consideration those who face(d) discrimination from a life partner who was not also a romantic partner
Leaving out or not taking into consideration those who have moved to a different area than where they used to live, and thus have lived in different social/cultural contexts
Leaving out or not taking into consideration those who are non-human or alterhuman, especially those who are not therians or fictionkin
Limited response options that assume the respondent has an in-depth, almost clinical understanding of their past experiences (see: those with memory issues – such as amnesiac systems – asked about discrimination they faced, those with difficulty reading social cues asked about their social experiences, etc.)
Limited or no elaboration given on questions that may be vague or unclear, especially to disabled respondents
I could probably go on, and maybe someday I will, but this should serve as more than enough as a starting point. The short version is that if you're designing a survey for a wide spectrum of people, you can't just make it for a handful of the most common colors and expect that to be enough. You have to actually dig into that spectrum, get a wide variety of voices, and then build your survey so those voices can be heard.