DFG is the item that allowed mages to face assasins
That item was the absolute best at allowing mages to adapt to who they play against.
Of course if your against an assassin you would need DFG
No way in hell would you try to slowly poke down someone as an AP when you can compete with their burst.
I think it was a huge thing that kept assassins in check
By allowing some mages to adapt and become assassins themselves they could compete.
Also DFG being removed is just one less of the few items mages have to build. Esp for CDR.
I get why this item was removed but Riot needs to replace it with something healthy that will help AP's adapt