Dynamus and Limbus was only end game and one one group could be in each Dynamis or Limbus area at a time. It's still different than what TOAU did by separating people from the regular world on a regular basis at all levels and having multiple instances of the same area going at the same time.

Where were these parties? What did they fight?

I'll never deny that TOAU gave people more to do.....

I started playing FFXI a week or two after its US release. Upon logging in I was greeted by some kind of city official in the industrious city of Bastok. I was told I was an adventurer, like all of the other play characters. I wasn't sure what that meant at the time. What I could do was quests to "help" the NPCs out (which helped me out). Some of the quests involved large groups.... Like "eco warrior" and "tour of gustaberg." In the case of "tour of gustaberg" there was no great reward but the quest got people together and got them taking a long trip together... It wasn't hard at all. Eco warrior was difficult to both form the group and complete (wiping was possible with the level cap) so you needed the right people (jobs?). Those people probably didn't go out of their way to do eco warrior but it was nice to check off of your list of quests and say you did it. The reward was a mild bonus. In both cases the party was formed for the sake of accomplishing the quest.

Speaking of parties.... Leveling up was difficult and jobs had to gravitate towards extremes to be useful. For example, almost every damage dealer subbed warrior for berserk and attack bonus and wore gear that maximized STR, DEX, and attack. WHMs wore gear that maximized their MP and subbed SMN or BLM to maximize their MP. A RDM/NIN, DRG/WHM, PLD/DRK, or MNK/WHM was not sought after by parties. Each of these jobs that gravitated towards an extreme came together in the party and relied upon each oithers strengths to make up for the extreme weaknesses that were bred. For example, a WHM/SMN can't take hits and a PLD/WAR can't deal dmg.

Official missions were used to advance a story of a shadow lord who had plunged the world into chaos some time ago and was supposidly returning. ROZ built upon that story by explaining how the leaders of Jueno were what remained of an ancient race who manipulated the shadow lord into being the shadow lord (if I remember right). COP also built upon that story by giving Altana an antogonist, using characters from the original game, going into details about the Zilart and Kuluu, etc.

Then came WoW. Then came ToAU.

I'm not longer an adventurer.... I'm a mercenary who does things for treasure. Every quest and mission involves talk of treasure. The whole reason white gate is attacked is because the monsters want some kind of treasure in the town (I can't remember what it was called) and sometimes they get it...

For the first time we have parties made up of all of the same job. I often participated in all DRG/WHM groups fighting colibri. BLM mana burn parties became common. The new jobs, PUP, BLU, and COR are all hybrids that don't gravitate towards an extreme. A COR is both a DD and an enhancer. A BLU is a physical and magical DD AND a healer... This is not like a RDM whose melee dmg was insignificant and who was usually a dedicated healer or nuker.

The story builds nothing on the original game and instead takes us to a whole new land that has as little as possible to do with the original game. Here there are no Zilart, Kuluu, shadow lord... The whole history of the game has been restarted in this land.

We now have instanced dungeons (assault) where a team is separated from the rest of the world for a short time to accomplish a mission. The only time a player character was sepaarted from the world in the original game was to fight a boss in a small area.

The missions were easy.... Anyone could do them. Backtrack to COP Diablo fight and no one was winning that fight without a good DRK and everyone knowing where to stand on the floor.

Anyways... ToAU and WoW have the majority on their side.

1. It was BARELY whispered in passing. The TOAU missions had nothing to do with the shadow lord and zilart who tied the original game and first two expansions together
2. LIKE WHAT? BLM burn parties were formed because BLMs were no longer considered a necessity in exp parties and there were mobs weak against magic in TOAU areas....the blob things in the volcano.\
3. There were no monk tanks prior to TOAU.....
4. Everyone zone is not an instance. Players from the entire world can get into one zone (theoretically) in a non instanced world.
5. I suppose the nation missions and TOAU missions were of comparable difficulty. But the nation missions were easy except for maybe the shadow lord (prior to TOAU).

1. Neither did rise of the zilart nor CoP have anything to do with the shadow lord, in fact they had even LESS to do with thim than ToAU did because they explain exactly nothing about him and are more about the ancient races and the gods, the shadow lord there is how you put it... whispered in passing? After the first cs that ties the end of the shadow lord into zilart there is nothing to do with him. In ToAU it at least directs you to his origin and goes into explaining the origins of the kindred (which the shadow lord is as are the demons that surround him).
2. Sly gave you a list of them, and as said they were not uncommon AT ALL before ToAU. Once again you are mistaking your experience for reality. Very few mobs would prove resistant to the way mana burns work, and they were very efficient parties... they didnt come around because of ToAU, ToAU just made them more prominent.
3. This is completely false, again just because YOU didn't know of them doesn't mean they didn't exist. Monks have and had access to a fair amount of -pdt, had high hp, and did a fair amount of damage. They worked perfectly fine as off tanks and would be used on occasion (merit is easy because the mobs die fast and you didnt really need a maxed out defensive tank).
4. You clearly don't know what instance means. There is AN instance of the zone south gustaberg, players being able to enter and exit that INSTANCE is irrelevant to it being an instance. Is it the common usage of the term? No. But the only difference between an instance of a regular zone of ffxi and an instance like assault is who is allowed to enter it. The reason why they are called instances is to distinguish that there IS more than one but even a single one is still an instance. Further, you failed to point out where the difference of importance is between having a limited number of instances (having to wait til the instance is cleared) and not. To the player the experience is the same, you go in with your party and only your party.
5. The shadow lord wasn't even hard before ToAU, you could solo the fight. Again, ToAU was comparable in difficulty to zilart (moderate intricacy). Zilart did have divine might and the like but those are not part of the missions. I can't think of a zilart fight that was notably more difficult than the harder points in ToAU (and the ToAU areas were notably more dangerous than were the areas that Zilart took place in with the exception of sky).
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