Why was FFXI so great?

[Volsung]

XI had content, both for hardcore and casual players (though the casual content took longer to come)

Hardcore: nm, endgame areas (sea/sky) with tiered steps to take and make progress, several different events that werent simple run straight through raids

casual: besieged (town invasion event with fleshed out npc general allies and enemies), campaign (always going capture the territory from beastment event), FoV (increased exp for targeting certain mobs), chest drops from normal mobs

not to mention excellent expansion storylines, RoZ CoP ToA WoG (good npcs)

Why abyssea ruined it? for years everything was geared towards 75, and a lot of "ultimate" sets that took lots of effort to get at 75, suddenly became garbage. Lots of people felt like all their time went to waste