[Serious] Please convince me gender is binary

[Jehanne]

No one who studies LGBTQ issues believes that "gender is binary".

You made that up. Transsexuals, by definition, see gender as binary. In fact, it is almost impossible for a person to get a letter recommending SRS  from  a psychiatrist who specializes in gender identity issues, unless their client has a binary view of gender. If the client doesn't have a sense of identity that is exclusively male or female, then a letter recommending SRS is extremely unlikely.

Pangender is a non-binary gender defined as being more than one gender. A pangender person may consider themselves a member of all genders.[1] The prefix pan is Greek and means "all".[1] Pangender is a kind of third gender, much like bigender, trigender, or genderqueer.[2] Pangender individuals may identify with gender inclusive or gender neutral pronouns instead of gendered ones (such as she/he or her/him).

Wikipedia -- Pangender