Some interesting parallels from a online game thats survived 20 years. D3 might well consider this case study and think about how to meet the needs of all their customers
https://arstechnica.com/gaming/2019/06/everquests-long-strange-20-year-trip-still-has-no-end-in-sight/
tl/dr
No new players, all level 110 Whales who can effectively solo the first 10 years worth of raids.
from the article.
qutoe from a everquest developer on fan engagement
“It’s damaging to not have a fan faire,” Longdale admits. “I’m trying to find the right venue. We are going to do something, but it’s not going to be a classic fan faire… The most value we had [in the past] was sitting down with guilds and going to dinner and just getting face time with players actually playing the game.” So though she promises an event is in the works, she insists it won’t be in the same form as old fan faires.
that could be interesting having a beer with IceX, and the rest of the design team. or it could be an incredibly awkward family dinner. hahahaha
Every year at GDC I try and give Brigby a high five, but we haven’t been able to catch up lol.
I just got in the office, so I’ve really only done a quick skim of the article, but I think Everquest has a unique double-edged sword on their hands.
One the one hand, no new players means they inevitably have an expiration date on their game. On the other hand, no new players also means they can focus all of their attention on the late-game experience and cater every change specifically to veterans. It’s certainly an interesting situation to be in.
Heh. The first year our team went, I only had the pass for the conferences, and this past year there weren’t really enough Community Management talks to make it worth attending, I’m afraid.
One day, though. One day that high five will happen! 
That EverQuest article is fascinating. Thanks for posting 
I think 20 years and talking about expiration date is like U-235 and halflife it’s a long tinykitty time!
If I knew that MPQ would last another 2 years I would buy a Stark right now.