I was asked the same thing by the professor who I had to see to get a referral to a gender clinic. It's policy if you have a diagnosis. Found out later that this clown had been instrumental in creating trans care policy in this country.
He suggested that the reason for me "thinking I was trans" was that I couldn't handle being gay and had to become a woman to legitimize being with men. Transitioning obviously being the easier option since us trans girls are so universally loved and respected.
In the second meeting we had I pointed to my genitals and said that these have to go. Dude looked super annoyed but that was it, the meeting was over and I got my referral.