One of two things is possible.

Transgender is what you are, regardless of how you identify and what you believe.
>Brain scans detect actual physical differences between cis and trans brains.
>Pre-HRT

Meaning, that Transgender individuals really are physically, and perhaps genetically, different, but very similar to typical LGB people.

Beyond the physical differences between LGBT & Cis heteronormative society,
A Transgender naturally deviates from the norm in personality characteristics.

For some reason, about .5 to 1% of people, varying by area and circumstance, ARE NOT naturally inclined to be the gender and sex assigned at birth.

The experience of a transgender is well documented; there is literally more evidence that Trans people aren't just mentally ill than there is proof that Christ even existed at all.

>.5% of your population is A LOT of people.

Please don't betray the trans community for short term political gains.