It seems to me that WoW players always concern themselves with future content more than the average MMO player. I suspect this is partially due to Blizzard's long but regular expansion cycles, partially due to the datamining and reporting industry that has grown around WoW and which relies on always being able to generate interest with something shiny and new. I'm certainly not immune to this myself - back in 2019, Classic was still weeks away from release when I wrote a post called "What Will Come After Classic?" for example.
For the past two to three years or so however, things have been pretty quiet on the Classic front. As soon as it became clear that Blizzard was developing Classic Burning Crusade, it was a no-brainer that Wrath would come after - there wasn't really any mystery about that. And the Season of Mastery servers were always meant to be a limited-time project with a defined end.
Now that this end is rapidly approaching though (at this point the SoM servers are due to shut down in less than two weeks), a lot of people are wondering: what's next? Many SoM players have found their way towards era, and while I've loved to see it grow, I think it's pretty clear that at least a sub-section of them is only seeing era as a way to pass the time until the next "fresh" server comes along. But when and what will it be?
Meanwhile in Classic Wrath of the Lich King, people are getting antsy about whether they'll have to deal with Cataclysm 2.0 soon. Blizzard sent out a survey back in September to gauge people's interest in a Classic Cata, which means they are definitely thinking about it, but at the same time that's all the survey questions really told us. This wasn't like the BC survey where it was obvious that they were already working on it and the question was just how exactly the transition was going to go down.
In some ways it seems like a no-brainer. People clearly dig this whole "reliving old expansions" thing, and Cataclysm is simply next in line. Presumably Blizzard has worked out a system by now that makes it relatively easy to revive yet another old expansion. Cataclysm maintains a bad rap, but people forget that for all that, Cata held on to more subscribers at its worst than Mists of Pandaria had at its peak, and many people look back at that expansion fondly by now, so there's likely to be a good chunk of players that would be happy to replay Cataclysm as well. Not to mention that even if you're personally not that excited about Cata, if you've made friends in Classic and they are okay with continuing into Cata, you may very well find yourself being pulled along by sheer momentum.
On the other hand... there is a lot of negative public sentiment surrounding Cata, so much so that annoyed forum threads and articles pushing back against the mere idea started popping up shortly after the survey came out. Even if you liked Cataclysm, it's hard to deny that the destruction of the old world kind of marks the end of the original "Classic era" (not to be confused with Classic era servers! 😉) and makes a potential re-run of the expansion seem a little less interesting simply because it wouldn't be as far removed from the modern game. I know there probably won't be another BlizzCon for a while, but can you imagine a live audience cheering for a Cata Classic announcement? The potential controversy it would create would probably not be Blizzard's favourite thing to deal with in their current position.
So... I'm honestly not sure about this one myself. At first it seemed like a given, but seeing a lot of the negative reactions around it and with Blizzard currently in desperately-trying-to-please-the-people mode, I'm not 100% sure they'll actually want to be that controversial.
What about Wrath Classic era servers that remain in Wrath of the Lich King forever? This is another subject on which my opinion has gone back and forth a lot. When Blizzard decided not to do permanent Burning Crusade era servers, I figured they were just going to plough onwards from now on and Wrath wasn't going to get era servers either. Then I saw people talking about them a lot and figured: hey, there's clearly more demand for these than there was for BC, maybe it'll happen. However, as I've spent more time on Classic era, I'm kind of doubting it again. As much as I've been enjoying my time on era, it seems very clear that from Blizzard's point of view, era is a bit of a nuisance: a game mode that doesn't have a lot of players but still requires resources to maintain (you'd be surprised by the amount of bugs that have been introduced to era by updates to other versions of the game and that then needed fixing).
WoW Classic producer Aggrend supposedly also told someone on the Classic era Discord that we're unlikely to see something like the Classic cloning option again going forward for technical reasons, so unless Wrath era was literally the only thing happening at the end of WotLK classic (which seems kind of unlikely), people would likely be forced to choose whether to stay or go forward, without any option to continue playing in more than one version of the game. I'm just not sure Blizzard is keen on adding yet another version of WoW which will only be played by a minority to their maintenance list. So I'm leaning towards no on this one, though one should never say never I guess.
What about the next Season of Mastery then, or other "fresh" servers of any kind? We haven't really had confirmation of that one happening either, and Blizzard devs that have been asked about it in interviews have been evasive, saying things like how much they loved SoM and how much they learned from it, without giving any clear indication of another one being in the works. I'll throw my hat into the ring for this one though and will say that I expect some sort of fresh start server to launch either around the time WotLK Classic hits Trial of the Crusader or when it's on its final patch. Whether Wrath transitions into Cataclysm and/or people get the the option to stay on a Wrath era server, there'll be people who'll find themselves longing for more of the "true" Classic experience instead, and yes, while that is available on era, the push for fresh servers and continuous progression is strong.
So I think there'll be fresh servers and a Season of Mastery 2 of sorts, though I think it will not be called that and will be quite different from the first one. Examples of what I could imagine happening here is a fresh Vanilla server but with Burning Crusade or Wrath talents, or a server with a three-year-plan to progress through Vanilla, BC and Wrath again in quick succession. Maybe even an actual hardcore server, what with how much publicity that has gotten recently! Basically nothing too crazy, but with enough of a twist to arouse curiosity from the masses. Just three months ago I wasn't sure whether Season of Mastery could be considered a success, but I think that having some sort of seasonal server running at all times will probably be in Blizzard's interest; they'll just have to make it more interesting than SoM was.
Finally, someone always brings up "Classic+" or continued development in the Classic world in the form of an alternate timeline or something. I already said back in 2019 that I considered this unlikely due to the risk and cost involved, but honestly, I've only come to view this idea less and less favourably over time. I've learned that Old School Runescape is a much more sandboxy game than WoW, so that it doesn't actually work that well as a model to emulate, and cramming more dungeons and raids into old Azeroth just seems like it would create problems left and right. People who continuously push for this honestly just give me the vibe of wanting to eat their cake and still have it too - as in, they want Vanilla Classic to simultaneously stay the exact same but somehow also have new content every couple of months just for the sake of having new content, without any real vision for how to actually square that circle.
I think in practice Classic will continue to be about rehashing old content with only minor changes, and that is fine - that's what we all signed up for after all. However, I think it will increasingly become a challenge for Blizzard to maintain all these different versions of the same MMO (something I seem to remember them saying at some point they really didn't want to do... yet here we are with three different game clients already), while the community will become more and more spread out and pulled in different directions.