Indeed. To compare launch content against WoW is not a feasible argument. WoW launched in an age when no comparable MMO even exists on the internet. Heck, it'd get away with releasing no content past level 50 (max 60) at that time!
Nowadays? A MMO will NEED compelling endgame for all kinds of players (casual content, PvE content, PvP content, cowclicker content, RP potential, completionist content, etc.) at the very start in order to keep its players. Regardless of what those older MMOs launched with, the fact stays that they launched earlier and will have an advantage in content. It's not a fair fight, so no MMO should enter the market expecting a fair fight. Make content or die.