Ill is not the word I would use to describe transgenders. But they are mentally unaligned with the sex they came with into this world, Ergo the term gender dysphoria. They can be a functional member of society like functional alcoholics who are unhealthily addicted to their poison yet still appear controlled. But we all agree alcohol addiction is not normal and unhealthy - capable of pivoting a person's behaviour to the irrational with triggers. So are transgenders who reject their body and wanting to be the opposite sex to the point of self-mutilation. We can pretend transgenders as 'normal', Even accept their idea of their Identity. But it'd be lying.