I don't understand what you mean. When I say "game play" I mean the how the game is actually played. Things like available weapons or reachable maps affect game play. Cosmetics don't. Skins and emotes don't make you play the game differently therefore they don't enhance "game play". Just like wearing a fancy shirt doesn't enhance the game play of chess.

Fortnite even allows you to enter competitive tournaments and compete for money without spending a dime. A player that spent $0 and is using the default skin is at no disadvantage vs a player that spent $1000.