First of all, thank you OP, for posting this thread. Clearly, this is not a problem that only affects a few animals. Many horses are just never going to be able to tie, for many different reasons.
I am the owner of a pullback. Luckily, as I have owned him and he has grown up a little and learned that I would NEVER put him in a situation where he could be hurt (whenever he gets the “worried look” in his eye, I calmly stand with a hand on his shoulder/withers, and repeat that I would never let anything I ask him to do hurt him, and in my brain, he understands this, whether it is my tone, my words, my touch, whatever. It helps.)
While getting to know each other, we had a few scary instances where he showed me his true panic mode, and I have decided that the risk of tying him is not worth the benefit of having a horse that ties. He is always held for the vet/farrier, but can be crosstied to tack up, I just make sure I have everything I need out and ready so that I don’t have to leave him too much. A few months ago, when he pulled back on me for the farrier, my farrier grabbed my horse and pulled back to make him mind his manners. Well, my horse did a backflip on the concrete aisle. I was lost for words. You can’t teach these horses “a lesson”, because in their minds, they are not being disobedient, they are terrified. Do we really need to force them to tie because it’s more convenient for us? I don’t think so! I love my pullback and I am glad for all the other pullbacks with wonderful, understanding owners that love them as well, as evidence in this thread.
Our horses make do with our quirky personalities and many flaws, I think they deserve the same respect from us.