You would probably get a higher response rate than 1.5% on "are you a potato" or "is your religion Jedi". The few youngsters who identify as "transgender" other than as a prank are mostly the children of social justice warriors who want a trendy boutique kid and don't care any more about the damage than they cared about aborting their first few children.
When my kids were in high school, they thought those surveys were a joke and answered accordingly.