it's not about "HEY! LETS BUFF THE SUPPORTS"
but more like, knowing exactly what to do, for example i play top/jungle/support.
i admit i have my fair knowldge of all mentioned roles, however as for the support, i go as a Tanky support, and my first item after Relic Shield is Sightstone, it's because of this we're always behind on getting that active of the item, and if buffing the midpath of every support item, then it's good, and when we finish the final build, the actives becomes stronger, which is nice.
Sight is the key to victory!
also stone.