I'm not saying that there has to be quests and wasn't necessarily saying that quests are a must, but quests are just a way of getting a reward for what you would normally do anyways. Just with a story and objective. Every game needs some sort of objective system whether they are labeled as quests, missions, tasks, etc. it doesn't matter. One big reason they make so many filler quests is to keep the player playing the game. If you were to take out all the filler quests from Skyrim or any MMO the game would be over before you knew it and also leveling would take much longer and players would need to "grind" much more to reach level up. What I wish is that we would be able to fix quests by creating new ways of accomplishing things by adding new game play and mechanics. Not just adding a small short detailed story on why we should "go to some cave and kill the trolls living there" or "finding the sacred herb to heal the sick person". There will always be filler quests in RPG's and MMO's because the developers want players to stay playing their game longer, while not having the time to make every single quest amazingly epic and awesome.
I think i'll answer your question with another question. Why does everyone feel the need for so many quests anyways? We all agree that quests are boring and repetitive so why are we trying to fix the boring repetitive parts of the game and try to make them interesting? Why can't we just get rid of 80% of all quests? The ones that are left are purely optional to the player with huge rewards. I think its a great idea to make the quests puzzles and with more lore but if the quest doesn't have something rewarding at the end then nobody will be motivated to do it. In the early days of EQ quests were very special the rewards were unique items that either looked really cool or had special non-combat uses. Some examples were a pair of boots that make you run slightly quicker, a shield that made you invisible, items that allowed you to return to you're bind location. At higher levels classes got excellent items for very difficult quests that could take weeks and weeks to complete.
By turning quests into a leveling mechanic instead of an optional game play feature you force the player to play the game through the eyes of a developer. Now you don't even have to explore the world, I find myself looking at the map half the time playing to make sure my character is running to the right place where the items are marked on the map. To make quests more interesting... get rid of all the filler quests that are just there for experience. Work hard on just a few quests and people will love them.
I totally agree that having filler quests just to keep people occupied is ruining a lot of games and looking at the map is something I do a lot also, even in new games like Guild Wars 2. They need to find a way to fix stuff like that. One things GW2 is doing right, is that they make the player want to explore the world itself, while having fun doing so and not going to an area JUST to finish a quest.