Basically the battle royale game mode was all they had as an identity. Almost everything else about the game is generic. The graphics look like every asset-flip from the last ten years, music is utterly forgettable, there's just no style. I hate almost everything about Fortnite's style but it does have a distinct one.

Compare Wolfenstein 3D to Doom, except pretend Wolfenstein never had the "Nazis" idea and you were just fighting generic soldiers.