Just a comment. In the 40 years I bred dairy goats, with one exception, I never had a buck challenge me. The exception was one not-too-bright youngster and he never did it again. Personally, I wouldn't keep a buck that was dangerous to be around. It just isn't worth it. If he was valuable, I would have him collected and then in the freezer he would go. But that's me.
I totally agree with you. Unfortunately the goat that challenged me wasn't mine, he was a goat at the farm where I keep mine. I suggested that the owner to sell him. They didn't want to, so they just put him in a separate area. Honestly, he was low quality and served no purpose. If he was mine he would be sold. I wouldn't butcher. There are thousands of more goats exactly like him you could pick up for a couple hundred bucks. If he was high quality, that would be a different story. Although, I don't know if I would want those genetics in my herd. A mean sire could throw some mean kids.