That is the question of the month or perhaps of the year. I'm not entirely sure myself either but my guess would be the combination of old players losing interest, although that doesn't explain why new players aren't coming. Well gmod is an old game and its player base has been on the decline for several years now. Still there's popular servers out there, why's limelight just dead compared to those?
See the discussions section of the forums for similar threads. Here's couple like this:
https://limelightgaming.net/forums/thread-28114.html
https://limelightgaming.net/forums/thread-27835.html
https://limelightgaming.net/forums/thread-27707.html
I'm in no way saying the server is as it used to be long ago, especially community wise. In fact the staff, players that I've seen on the server during the past week have been more than welcoming and friendly!
Note that I'm basing the following to my experiences few years ago as that's when I was most active. Maybe the toxicity within the community has something to do with it. I don't want to name anyone but to put it bluntly, I do remember some staff members seeing every rule as an absolute truth and not realizing even though some role plays sometimes require one to break some rule that doesn't cause anyone any mental harm. Instead too restrictive rules for an rp server profiled as a semi serious rp server can be harmful limiting people to a narrow mold when it comes to role playing. I remember being scared of touching weapons due to the atmosphere around me. I told my friends sometimes on teamspeak that you can do the shooting because I can't as someone might be watching me and funny thing is that on way too many occasions I was being spectated and it was always the same people doing it. It felt like they had a feud with me and only followed me around to make themselves feel better so that the bad guys get what they deserve since they broke the 1000 commandments of my holy book, the rule book. At some point I stopped completely all aggressive rp and it was never my favorite part of role play, I just preferred to do little bit of everything.
When it comes to the normal players it's not all that welcoming for a new player to keep on playing if the community doesn't welcome them, openly show their distrust and hate towards each other both in game over ooc, on forums not to mention the excessive player report culture there at least used to be few years ago.
Also maybe people didn't like the maps that were in place for a long time (rockford for example) or the map rotating, who knows?
I don't know about others but I do still love the content limelight has to offer on the server. Just wish it had a healthy player base.
