Acquisition rates for epic quality gems (specifically Queen’s Garnet) are in no way keeping up with the demand. Prices for individual red gems are still over 5k gold each on my realm - I would assume this is the case on most others as well. This is especially problematic for those who only PVP, as they have no access other than the AH to anything but resil/spell pen options.
On an otherwise unrelated topic, people are not running Twilight Dungeons as much on mains since most have the gear they need already. These dungeons benefit from having at least a mix of geared players to offset fresh alts and/or new players coming in.
My suggestion to benefit both of these concerns would be adding the epic quality gems to the Obsidian Fragment vendor. This would both increase participation in Twilight Protocols as well as bring gem prices down to a more reasonable level.