This caused me quite some headache, yet the suggestion has been accepted (with a twist).
The quest is actually rather tedious and I can understand if majority of players rather want to skip it.
I believe this compromise will make community happy:
1. Item "Bristia Armguard" has been added to Summon Stone "Elite Bristia Weapon Summon Stone (Event)".
2. Quest "[Selva Sub] Selva, brought her power back.", added additional rewards: 15x Karin's Vital Potion, 5x Elemental Jewel
This gives players the freedom of choice yet the quest won't feel useless due to the changes.