I feel like placing identities into hierarchies always ends up controversial. Like non-binary is technically under transgender because transgender just means your transitioning from your assigned gender to something else; but a lot of non-binary people really don't like being called transgender instead of non-binary.

At the end of the day, the words meanings are a subjective experience that cannot be directly observed or compared. So functionally all self-identifying terms exist flat relative to each other because there will always be contradictory definitions that you can't rigidly settle on without ignoring significant groups of people.