Because now you have a giant mountain (roughly a triangle), and the giant dinosaur (roughly a triangle) pointing more or less together. This helps focus the attention / energy of the shot.
It's definitely subtle, but a good amount of film making (or hell, photography) is that way.
Everything on screen matters. Modern Cinema is a HIGHLY evolved art form. If you have any interest in this at all, YouTube user Every Frame A Painting publishes, short, easily digestible, and well-produced YouTube videos about this stuff that are eye-opening.
It's definitely subtle, but a good amount of film making (or hell, photography) is that way.