I wonder if this is similar to how musket battles were fought in the american civil war era, with soldiers lining up across each other in a battlefield and taking turns shooting at each other. I hear they did this because the rifles were very inaccurate so it made sense to use a bunch of them at the same time as an area-effect weapon, in effect like a gigantic shotgun.

Until someone got better weapons and suddenly the "rules" of the battlefield that dictated standing in lines across each other made no sense to follow anymore because the original principles that dictated those rules to be good were not valid anymore.