During the Stella O'Malley documentary, I was struck by how childlike the transmen were. The things they said, their demeanour. I couldn't imagine them, for instance, holding down a full-time job, having a mortgage, etc.
I would assume that if you are arresting physical development, mental development and emotional maturity can't help but stop with it.
Look at jazz Jennings. Appears to be a permanent adolescent.