"Everyone" can't be bored, because not all players have even reached level 90 to start playing around with the Island Sanctuary. You're also discounting those who have reached 90 and haven't yet started with this content, as well as all of those players who seem to enjoy it and haven't tried to max out to level 10 within the first month.
So, not "everyone" at all.
Out of the entire population of active subscribers, you may actually interact with, what, 150-200 of them, max? So "everyone" in this context is self-selected: you don't actually hang out with people, or converse with people, about Island Sanctuary unless you've already established some form of relationship.