About 10 years ago, author Theodore Dalyrimple gave what I think is the most cogent, logical explanation I've heard--though he was not even addressing the issue of transgenders specifically. He was making a point about political correctness. I think it's a spot on diagnosis for the motivation behind the left's Alice in Wonderland LGBTQXYZ agenda.
"In my study of communist societies, I came to the conclusion that the purpose of communist propaganda was not to persuade or convince, nor to inform, but to humiliate; and therefore, the less it corresponded to reality the better. When people are forced to remain silent when they are being told the most obvious lies, or even worse when they are forced to repeat the lies themselves, they lose once and for all their sense of probity. To assent to obvious lies is to co-operate with evil, and in some small way to become evil oneself. One's standing to resist anything is thus eroded, and even destroyed. A society of emasculated liars is easy to control. I think if you examine political correctness, it has the same effect and is intended to."
"Everyone has a right to health; depression is unhealthy; therefore everyone has a right to be happy (the opposite of being depressed). This idea in turn implies that one’s state of mind, or one’s mood, is or should be independent of the way that one lives one’s life, a belief that must deprive human existence of all meaning, radically disconnecting reward from conduct. A ridiculous pas de deux between doctor and patient ensues: the patient pretends to be ill, and the doctor pretends to cure him. In the process, the patient is wilfully blinded to the conduct that inevitably causes his misery in the first place. "
After reading your post, I examined my OWN inner feelings and past responses to THE sexuality issues. Sadly, I have somewhat “succumbed” to political correctness ( through silence) from time to time, inorder to not appear to be too rigid in acceptance of other lifestyles, thus I would be “humiliated” by expressing my opposition to what I believe is deviant behavior. My daughter in law and I recently had a discussion, in that I was watching a tv show with my grandkids, a Disney (teenage targeted program with the promotion of homosexuality.) I immediately made my gkids change the channel. Later I mentioned it to my DIL and told her how shocked I was and sorry I wasn’t more careful as to what they were watching. She informed me that she and my son had already had this conversation with the kids(ages 13, 11, and 9) and that they were aware of the different gender options and that it was okay. I was sick to my stomach, but said nothing. So there it is, I was humiliated.