I find the title a little misleading as their is really no data to back it up, only personal experiences.

There are many folks out there still just starting Eureka and if an instance is literally dead since I am lvl19. I am hopping to a new instance that has Fafnir and higher in spawn window, chaining those mobs to pop them with a party of 4 or 8, as its optimal. When I re-queue, I rarely get into the same instances as before, unless it is literally non-peak hours. Each instance having a wide range of players 1 - 20.

With the content only a week old and no adjustments yet with a hotfix, it is just assumption at this time and SE has all the data... Players will definitely drop Eureka once they have what they want. However, with the ease and accessibility of this content compared to previous Relics, I am hearing more and more players wanting to do other job upgrades on alts than deal with the Tome limits on Mendacity.