To be perfectly honest, the server isn't doing really, really good, but it's not doing horrible either. Yeah, in the past there were more players, but- in my opinion, at least- the tight-knit community more than makes up for that. Partyzone has made some mistakes (no offense devs and everyone who has made this possible, you're all amazing and tysm for everything), but there are still those games that are still amazing. Think of Murder. I have never seen a server with a better version. Some could argue the same for DG, even though there can be bugs at times. Like stated by others, let's not forget that even though there are still new MC players coming, Minecraft itself is dying. Microsoft can also be blamed. I've heard from several people that they have killed MC with all the new updates. Sure, there are new blocks, but nothing can really beat the earliest versions.
About everything listed here on this thread has to do with the decline of PZ and Minecraft in general. There are those who talk about "fixing" things and bringing the whole server back to where it was (and I will admit I was one of them), but what can really be done about Minecraft? Where PZ is concerned, yeah things can be improved, but in the end, how many players could be pulled in? It can be argued that there is quite a number considering the popularity of MC, but that depends on the player. Say PZ did make a great version of a game that was considered better than other servers' versions. Some might leave, but there is also some who wouldn't give up their stats on another server. I'm pretty sure I saw a comment about the players changing, which is also a problem. I know I haven't listed everything wrong and that some of you might disagree, but there are some things we can do and there are some things that we have little to no control over.