I do not log in much due to a combination. A lot of the people I played with have begun to log in less and less. Others burned out entirely, and some of it is also due to the fact I am just busier in life.
I also find quite often I log in and find nothing compelling to do. The server has formed, once again, a very strong "clique" of people who have far more time to log in every day than I can possibly have between work/social life balance. Though I am not crying favouritism here, I understand that obviously people who log in a lot are naturally going to be involved in the most plots, it only makes sense.
But it does feel challenging sometimes to "Break in" to these cliques or groups. It isn't that they are unwelcoming or mean players, but they tend to do everything off in their special spots, or club house areas away from the general population of new or older returning players. It is often that I see something happening between players or some plot begin, only to have those players teleport off somewhere where no passerby can possibly get involved or socialize. It is a subtle form of "gate-keeping" that I do not think is intentional, but it doesn't drive inclusiveness. I tried to introduce my IRL girlfriend who used to RP on NWN1 back in the day, to this server. As a completely new player she felt like none of the more established players wanted anything to do with her, even when she approached a camp fire or tried to have conversation she said they often walked off to somewhere else or teleported out to avoid the rest of the population being involved in any RP they were doing. She got to about level 10 before giving up and going to play ESO instead. I know this is the reason a number of my fairly often companions in game have left as well. They feel like they are being intentionally left out of things, not by the DM's, but by the players themselves, though I must stress I don't think that this behavior is intentional to drive other players away.
This could be solved by potentially removing the teleport spell, or, barring that, giving more reasons for players to socialize with newer or returning former players. Whether this is by developing better social "hub" areas, or by perhaps putting incentives out there for mentorship of some sort. I am sure ideas could be brainstormed better than anything I can say here.
I think the other reason, and one I've mentioned before, is that all the DM's now seem centered around either Euro time zones or eastern time zones as opposed to the PST time zone they used to be in (which is back when I used to get a lot more plot direction.). I find when I can log in, there are no DM's and no events. I get to hear about all the cool events, but they all happen at like 6-7am my time, when I am obviously not going to be logging in as I work during those hours often.
DM coverage definitely seems to have been skewed to one specific time zone which leaves a lot of other people in the dust. Eventually the lack of ability to be involved in anything useful creates a slow burn out. But I don't directly blame anyone or anything. I have been here on and off for over 10 years now. I am older and have more going on, I don't really have the time to always be keeping up with this stuff anymore either. I am glad the place is still around though.
Also, on an more personal level I wish we had 100% RCR every 6 months or so. There are so many updates and new spells and things it is super hard to keep up, and as someone who has done my fair share of grinding it doesn't really heavily appeal to me so much anymore to reset my level 30's to level 20 just to re-select some spells or change some feats due to updates.
... just kidding!), so... for those that don't have an RP reason to go to those, it tends to be SOL time for them. The market in East Gate will usually have players visiting, but it's usually just them perusing the vendors. 
)
We're talking hundreds of hours, probably.