Absence of end-game content : the downfall of every MMO.

[Aragor]

WoW had Onyxia and Molten Core at launch. UBRS wasn't until months later. You had Scholo/Strat for "endgame" regular dungeons, and 2 raids. Not too different than FFXIV has now.

UBRS wasn't until you got the ring-key. Period.
I can't believe you're comparing MC/Ony to Coil/Primals. Coil is like half of MC at best and the Primals aren't worth doing once you've beaten them down once because what they drop is worthless compared to too easy to get Relic.