We hope you didn’t spend too much time farming up Shards of Domination in World of Warcraft on the basis of future-proofing against more difficult content. A post on the game’s official forums confirms that the current plan is to have Shards of Domination straight-up not work in the game’s patch 9.2 content, which means the new raid (Sepulcher of the First Ones), the new zone (Zereth Mortis), and all existing dungeons and PvP (that one is self-explanatory).
Keeping the approach somewhat odd is the fact that the Shards will still be turned on in the Maw, Torghast, and the Sanctum of Domination raid, making this an odd mid-expansion form of borrowed power that players have already pointed out didn’t even last for the entirety of the expansion. So if you opted out of this particular system when it was introduced, you’re likely to feel quite vindicated at this point; if you spent a bunch of time farming these shards, you’ll probably more than a little miffed.