Apparently you have not idea that there is a physiological reason that gender dyshoria exists. Depression is caused by seretonin imbalances or other physically measurable 'chemical' imbalances. Same can be said for other mental conditions or any other number of conditions within the body. Gender dysphoria is caused by brain wiring that is out of sync with the body most likely caused and speculated to be caused by hormone imbalances while developing in the womb according to some experts.

By the way Gender Dyphoria has been removes as a 'mental disorder' quite some time ago it's not it's own separate classification according to the DSM.