[Update]: It's official, Fortnite has made the "Zero Build" mode a permanent new addition.
As a part of a recent and absolutely bizarre storyline, Fortnite removed the ability to build things in its default game mode. I fully expected this to be a small experiment that might eventually lead to an additional 'no builds' game mode, but as it turns out, that one might be coming sooner than expected!
While no official announcement has been made just yet, multiple dataminers have discovered numerous references to 'no builds' modes in Fortnite's files. So if you're a fan of looking at landscapes uncluttered by massive fortresses, you'll be happy to hear that the 'no builds' setting will likely be made available for solos, duos, trios and squads!
Considering how divisive the whole building element is among the Battle Royale crowd, I'm inclined to believe all of this isn't just some sort of relic in the code and that it's truly evidence of Epic choosing to mix up Fornite's gameplay yet again. After all, it does make a lot of sense for everyone involved. An additional game mode doesn't hurt those that enjoy building, it makes Fortnite a lot more attractive to those that don't, and I highly doubt Epic will complain about having an even bigger playerbase!
Whatever the case may be, I'll make sure to let you know once the official announcement goes live. Until then, have fun with all of the new stuff!