"Spray and Pray" has never been doctrine, a training step, or an accepted TTP. It is the response of a scared conscript with little training in an alien environment when being shot at by a hidden and sneaky enemy.
There most certainly is an application of suppressive fire to enable maneuver, but that is something else.
There actually was a study that pulled data from WW2 and Korea that pushed us in the 5.56 direction, in which the data indicated that whichever side of a meeting force shot more rounds (regardless of caliber), was usually the victor. Interesting ripple in small arms development and employment, certainly, but it did not start a training cycle of "Point toward loud noises and pull trigger until magazine is empty".