All guilds end up needing a bit of backfarming here and there, the current situation in Tturuj is entirely different.
Each boss drops 1 random class tome. There is a way to fill in missing tomes, but the more you use this method the more farming each successive tome requires.
I'd wager that if classtomes/opuses had all been in game and dropping off all appropriate mobs from the start, we would have 90% of our class tomes and 30-40% more opuses than we do. We could be done with turuj other than Rujik in a matter of weeks. Instead, we will basically be farming the zone indefinitely unless another method to gain these tomes is added. We can't really ask to suddenly have all tomes in game, but placeholders would help to minimize damage even though we are already mostly done with the zone's loot.
Its fun to raid never before seen content and get new phat loot, but in general the guilds that come after have it far easier.