But how precise is it? Eye tracking may be good enough for foveated rendering, hand tracking good enough for pushing buttons, but how does it compare to handheld controllers for drawing something in Photoshop?
Drawing is a task that is more like aiming - attempting to hold your gaze at a precise location for a period of time. It is possible, but you are fighting against the natural saccade pattern of your eye and it becomes tiring very quickly. You can expect fatigue / eye-strain within a few minutes.
A new platform certainly doesn't have to be better at every task.
Even 20 years ago, a professional digital illustrator wouldn't try to draw everything on screen with a mouse, they would have a tool more suited to the task, like a Wacom tablet.