Its all about access.
There are still large scale, epic/legendary quests even in the latest expansion of wow and similar to the old epic quests of Everquest unless you are in the right sort of guild, without the right sort of support your chances of completing the quests are close to zero.
EQ Cleric Epic - Water Sprinkler of Nem Ankh: My own personal highlight, the quest line took me months to complete (I am 'casual' in my play style), and once I completed I had a grin on my face for weeks to come.
It is also worth noting that in the original incarnation the final step of the Water sprinkler was quite a toughie, the final stage was simplified twice.
Originally the creature you needed to kill was dragon being on a 3-7ish day competitive spawn in the back end of a high level dungeon. So either you needed scouts in the dungeon to see if the mob was up and when it spawned call your guild in (if it was within your "prime" time), or you needed to camp at the spawn loc with support to keep everything clear and hold the spot. Remember this was a competitive spawn in an open dungeon. 24hours a day, mobs spawning every 20 mins or so to relieve the boredom.
Servers were world wide, so euro off time was generally either west coast US and the Hong Kong. Server and guild relations were key to either an orderly queue (a list) or KS'ing, "training" and lag inducing madness.
This sort of final step of a quest induced all kinds of drama, little of which was epic.
Myself, having completed this quest after they had "dumbed" it down once, so now the final creature spawned in an open zone (skyfire), rather than Sol B, after a 6 day 14 hour camp, yes it felt good. More so because so many people helped, stopped by and chatted and helped pass the time, mostly though I felt tired and very shortly after I went to sleep...
The quests have not been dumbed down, far from it, the legendaries in WoW for example require friends/community/guild to get together do something epic and it takes a while to achieve.
What has changed is access and definitely player expectation, not everything needs to be epic, you don't for example generally have a Sunday roast every day, but you do like to eat. Players want to log on and play, be doing something meaningful within 5 minutes, the "McDonalds" MMOs... which is why everything is metric'd and marketed and pyschanalysed.. it is less like play and more like psychology of play.
Whichever way, you certainly don't need to have to camp Ragefire for 6 days only for him to spawn at 2am on a tuesday morning, all your guild mates to be asleep and then have to watch as <Stars> come in and trounce your camp...
But hey we stole their mod rods at Kael, so honors even
(not checked for spelling, missing words, or grammar)