I would say that the relic concept was flawed as well and then they made Abbot and the sigil system was worse. At least with relics:
1. You could trade them in;
2. You could use them for more than just entry to the raid, there were some useful equipment to be had in exchange;
3. Of course, the quests, like PoP were hugely popular and made obtaining relics easy;
4. Perhaps it is just me and lack of the same amount of experience in necro, but the drop rate for relics seems to be higher than sigils; and
5. DDO is not supposed to be a grind.
I just look at it from traditional D&D ("old-timer" pnp player) eyes and think - I should really only have to run the quest once to advance my story-line.
Thus, although I dislike re-running the Vons and DQ to raid - I "get it" from a storyline perspective. I also understand that people run Titan and Reaver because they can farm it instead of re-running pre-reqs. As for giant and necro, to me, it can detract from your story-line / role-playing sense of adventure. All that being said, if they had made the ultimate raid worth the effort, people will suck it up.
Making something "tolerable" to do in order to advance to the next stage of a quest / raid does not mean that said portion of the game was a success, well thought out, in line with expectations of D&D transalted on-line or something that should replicated.