They are more like a memory of those raids that are gone now. Makes you feel like "i was there at that time" Its more of a trophy in the end, as shaders were granted on any completition / armor drop anyways. But considering they dont impact gameplay or puts players at a disadvantage...they dont especially need to be brought back, let some players who where there having something special in memories X) Its borring to have almost nothing that feels unique in d2. D1 was like that and it created so much joy when looking at your vault and earned loots and cosmetics. Hope you understand my pov, and i dont say that because i own all the previous shaders, i am missing some too...but thats how it is and its great like that.