When the a player walks around with the "View bobbing" option turned on it´s supposed to move the item like without an item or the way it was in 1.12.1 but it not the same. It moves almost nothing while walking or running.

Not entirely sure if that´t work as intended because the player´s camera already moves different on 1.13 than 1.12.1 but there something wrong. With an item the hand moves less than without it.