Blizzard have announced they will be nerfing Aberrus trinkets in patch 10.2 and have already applied the changes on the PTR. This is to avoid players having to run old content due to the relative power of the previous raid’s trinkets. 

PTR (Source)

The Guardians of the Dream PTR has been updated with the following changes:

ITEMS

Developers’ note: As players prepare to delve into Amirdrassil, we are adjusting several Aberrus trinkets to account for changes to tuning targets and philosophy as well as to mitigate effects which have proven simply too synergistic with class power. As with Vault of the Incarnates, we want to avoid scenarios where item power could drive players to continue running old content that they otherwise would leave behind.

Rashok’s Molten Heart mana restore reduced by 70%, healing reduced by 50%, and Versatility reduced by 20%.

Beacon to the Beyond damage reduced by 11%.

Ominous Chromatic Essence secondary stat granted reduced by 5%.

Neltharion’s Call to Dominance duration increased to 20 seconds (was 10 seconds), but primary stat granted reduced by 50%.