I always interpreted the bot to be more like classic animatronics where it's legs, be it that the joints have been welded together or just replaced with steel posts, are stationary, acting more as a stand, and Henry just built it or repurposed another endo into it with the sole intent of setting it off in front of himself the single time. Like a mounted gun with one last face mirroring your own with which you can sympathize in your last moments. Love the mask interpretation though, and the density of the body mechanisms. Really impressive take on what Scott might've modeled it to look like if he had.