I haven't seen a lot of chatter around live-service games in Patient Gamers communities in general over the years, but from what I can tell, very little of the Warcraft community made it over to Lemmy. I can think of a couple possible explanations for that.

First, because everyone uses Discord for voice chat over WoW anyway, with the Reddit exodus last year, Discord was always a more natural fit for discussion. Second, /r/wow has increasingly become a place for discussion around the game among former players, especially after Shadowlands. Seeking out a new space on Lemmy and actually participating in the necessary, proactive contributions to grow a community requires more enthusiasm than I think the jaded players have.

It certainly feels like there are fewer MMO players, but I'm not sure. I think we can be certain that younger players are being captured by different forms of live-service games though (shooters, various gacha) rather than traditional MMOs.