The amount of people on Agnarr is nowhere near a game breaking population. The issue stemmed from the fact that there is always that percentage of people that
a.) Will grief all the people around them no matter what
b.) Will assume that all content is for them and pursue it
c.) Will find a way to profit from the needs of others on the server
You can bring up krono or something else maybe as a potential issue. The population though is not the issue. Quests like this will always be contentious and you have to plan well ahead of it. This was a key to a zone where you need a raid and the loot is not that great and will be replaced at a known schedule. Think about there being a game like Pantheon that is strictly open world and a quest like this. If it slows down any other guild by you cock blocking a quest line they are going to do it and fuck anyone from getting to it.
I really am not sure if you played EQ at any kind of bleeding edge level. You are naively unaware of what was involved in EQ when it came to raiding (end game). I know you claim to have played both blue and red servers but to me your usage of those terms makes it sound more like you did P99 and never played Live expansions until well after they added instancing and removed any cockblocks.