I feel like you’re missing the point. Maybe I wasn’t clear. Yes, Lemmy World does use it, however it’s a feature of Lemmy itself, not just of Lemmy World. Lemmy World is just one instance of Lemmy and they all use the same markup.
My point is calling it the Lemmy.World markup is inaccurate and potentially misleading. Lemmy is more than just Lemmy.World.