Fortnite does have a few broken skins, and the most recent one is the Tsuki skin. This skin lacks a proper texture, thus ending up with a white appearance. Since this skin is entirely white, under proper circumstances, it's almost invisible.
Although Fortnite isn't a pay-to-win game, it does end up releasing a few items in the item shop that are comparatively better than the others. Anyone possessing such items gains a competitive edge over other players.
Is the Fortnite Tsuki skin really broken?
For now, yes, the Tsuki skin is broken. As demonstrated by x2 Twins in their YouTube video, the Tsuki skin ends up blending really well with the environment because it lacks a human texture. Players fail to notice the skin entirely and consider it to be a part of the environment.
Although it won't be hard to spot this skin in the forested areas of the map, it may get difficult to spot this skin in the areas where there are buildings. Since the Tsuki skin is completely white in color, it blends in properly with almost any white background, and players fail to notice it completely unless they get too close to it.
There's a human style that is scheduled to come to the skin sometime soon, but there's no exact date for it as of now.
The Tsuki skin is almost like the superhero skins from the Boundless set in Fortnite Chapter 2 Season 4. Those skins were completely customizable, and players often resorted to a full black-on-black version of the skin in Fortnite.
Since the skin was fully black, it was absolutely invisible in the shadows and difficult to spot in dimly lit areas around the map. Players took advantage of this and sneaked their way to a victory royale.
This skin also happened to be a pay-to-win skin since players had to purchase it separately. Something similar happened with the Toy Soldier skin as well. The Toy Soldier skin was completely green, and players had a hard time spotting it in the greener areas of the map.
The Tsuki skin may be broken to a certain degree but isn't as broken as the superhero skins from Fortnite Chapter 2 Season 4. Epic Games will probably tweak the Tsuki skin soon in Fortnite, keeping the skin away from any sort of controversy that may or may not come up.