My TWH mare is the quietest horse I've owned. By far quieter than the QH I had. Calmer than 2 of the 3 Belgians I've had.
Delight Bumin Around is her maternal grandfather so I don't think the generalizations are worth much. And she certainly wouldn't gait herself into a tree.
I don't have to halter or tie her to put fly spray on or run a rasp over her foot real quick.
She tends to spook in place and it's rare. When she does she will often turn to me like she's double checking to see if I'm still there, looking for a second opinion on the scary thing maybe.
I was kinda taken by this picture of Walktime Charlie. His eye looks dead. I get the impression he has shut right down to get through it all.