Same as many above really.
Most likely we've all had a good deal of time to explore the mechanics of NWN to the full, and thus only leaving the surprise in what other players/DMs can come up with.
Gave the answer itself, didn't it? Hanging around the tree is dull to most, because you know what'll happen. Going out to fight and gain a level is dull because you've seen that kind of fighting tons of times, there's nothing new to it.
That's what keeps me away. The knowledge of what's going to happen really.
Of course, the whole purpose with a server and with its staff is that this shouldn't happen, and kudos to those that work against this situation.
Honestly, and I'm not pointing fingers or blaming anyone or anything, but what I've seen work before was simply lots of quests, to give the game a whole new turn, players would never know what was going to happen today, thus it was exciting and new.
The DMs here aren't inactive so it's a limited improvement that can be made though.
Furthermore, I, as a rather new addition to the server lost my appetite to spend hours on a day due to finding myself ignored at times. I'm not whining, just explaining.
During quests I'd have been more willing sitting hours online a day if I didn't get the impression that I had to stay online as a wee one for a year+ in order to simply get response during quests.
To be fair though, it's only some quests I've experienced it with, most quests have been fair to even give attention to the midgets.
If midgets aren't enough to stop whatever evil overlord, then atleast let them get beaten to a pulp with style, better than just e.g. casting Bigbys on them and letting them stand there for the remainder of the event.
Just my five cents, no fingers pointed anywhere.