I kind of figured that was the case since this place looks like an island but not one that actually exists, so it's kind of the first world since Watopia that could be expanded without constraint. Pretty much everything else they've done has parameters (even NYC, although their decision to make it the "Central Park of the future" was a cool way to add new challenges and options.) Watching their teaser video, I couldn't help but think of Westworld's introduction of "Shogun World" on the show - the atmosphere they create in the video is just reminiscent of that part of the show.
On that note, I wonder if Zwift could ever expand beyond its current format as a training app. And by that I mean if it could ever become more like a real MMRPG for cyclists, where you could actually move through the world as, say, a bikepacker on genuine multi-day journeys. Right now, if you stop a ride, when you come back in you have to start over. But it'd be something if they ever got it to the point where you could take a virtual bikepacking trip where you could ride from one location and stop at a certain point and when you come back in, that's where you pick up again. I think to make that viable, they'd need the game to evolve where the worlds become less finite than they currently are. It'd have to be more like a real world building enterprise than the training app it is now, and I'm not sure that's what they'd even want it to be. I don't play any of those games, but I do know they are usually massive enterprises that need more users than Zwift has right now to be viable, so it may not be a possibility. But I think the idea of it is kind of interesting.