I do agree with you on this. I was watching it all unfold from right in the stall where it happened. I was talking with my friend and she was in the horse’s space, and she kept kind of picking at him, poking him in the chest, patting him emphatically in different spots and laughing when he’d pull a nasty face at her. I didn’t say anything because, hey, it’s her horse. I figured she knew him better than me. Then she did it one time and wasn’t really paying attention to his reaction and I’d just gotten the words, “You better watch him,” out of my mouth when he attacked her full on. I saw it coming.
The thing is, she raised this horse and they had an antagonistic relationship the entire time. Even as a baby he’d pin his ears and bare his teeth and come at someone. He actually went after someone while he was being ridden. The person on the ground was trying to fix a keeper on his bridle and he nipped at her. She kind of popped him lightly on the nose in a “stop that” gesture and he literally took the woman to the ground even with the person on his back trying to stop him from doing it.
He also came over the top of his stall door once and bit a little boy on the head that was just walking by.
I think something was wrong with him, and the way my friend managed and handled him didn’t help matters.