of course not, but not very many narrow chest bodybuilders before the hammer strength machines came along
fact is he doesnt do barbell presses and looks to have a narrow chest,
Kai still barbell presses and has a wider fuller chest

Take this comment kindly please, its not an attack or anything...
But this post is 100% fallacies, it doesnt matter what Kai does, it doesnt matter how chests "looked before hammer machines", the shape of a muscle is never determined by the different types of machines you used to stimulate it with.
Other than that, his chest looks great but this is a side shot, from the front he is still narrow.