In my opinion, there is always going to be a potential difference between the speed or direction of the ball and the pitcher's ability to catch the batted ball when approaching the body and especially the head.
Whether with a composite, aluminum, solid core or hollow, wood, or any bat, there is always the same chance that the batted ball will somehow not get stopped due to the difference of abilities of the pitcher to field the ball, batter's strength, bat speed, ball speed, pitch location, or one in a million shot.
In my opinion, if you want to mitigate the potential for head injury, pitchers should wear head protection.