Nerdy applause for your use of the word "colanging." LARP (live action role-playing game) would probably fit well in #worldbuilding. What about sandbox type games, like minecraft and the like, where people build communities and worlds, or cities and skylines? Would that fit in with this tag, or would it muddy the waters?
I'd put LARPing in the same general category as other games, like tabletop RPGs, and you can have just as much depth in worldbuilding with any of them, so worlds you've created to LARP in are certainly welcome. Games like Minecraft blur the line between games and level editors, and can be viewed as tools to help worldbuild. I'm certainly not "in charge" of the tag or anything, so even if I was annoyed by a swarm of Minecraft posts, I wouldn't be the arbiter of what can and cannot be in the tag. Though I'd say taking advantage of the ability to double-tag posts would be useful for such things, so such a post could be tagged as #worldbuilding and #minecraft, so users can decide whether to keep them or filter them based on their interest.