My personal theory--and I only speak for myself here--is that the sheer uncertainty of the time in which we live has made people more sensitive and defensive of things they've always taken for granted or assumed to be true. They look to things that offer permanency for comfort.
This does not wholly explain transphobia, of course, and I certainly don't believe it's a predominating factor. Nor does it make transphobic behavior excusable at all. But the surge of trans rights has sadly coincided with an era in which people crave stability more than ever.
If all people have generally ever known are very rudimentary and incomplete definitions of sex and gender and those definitions are presented to us as irrefutable and they're intertwined with personal identity and culture, there is bound to be anger and confusion.
And yet, that is the far extent of my charity on this topic. That's about as understanding as I can be. I can understand some of the anger and confusion, but that does not explain the refusal of grown adults to engage in good faith and learn about what they don't know.
When someone is confused and open to learning, you can tell. They want to better understand. (They also may put labor on trans folks, but that's another issue.)
But the people who approach in bad faith, with venom and an intent to harm? I have no patience for them. Nor should I.
But the people who approach in bad faith, with venom and an intent to harm? I have no patience for them. Nor should I.
So, if you're upset and confused and frustrated that the scientific reality of sex and gender aren't quite what you were taught, I'm marginally sympathetic. But the humanity of trans and non-binary people is not justified collateral for willful ignorance. You need to learn that.