Gjallarhorn has been the big prize that keeps players pushing through nightfalls, raids, prison of elders and anxiously awaiting XUR's arrival each week. I didn't feel 'excluded' when I didn't have a Gjallarhorn only driven to obtain my own.
After finally getting one, I didn't and don't exclude players who don't have one. On the contrary, I feel obligated to help Gjallarhornless players to kill Crota, Atheon and Skolas etc.
I don't know what Bungie hopes to accomplish by nerfing exotics? What's the 'big prize' going to be that keeps players signing on & pushing forward? With a few weapon parts, Motes of Light & Glimmer, a player can reforge a legendary weapon into a suitable substitute and not have to choose which exotic to equip.
Stupid idea Bungie!