What makes games interesting as a storytelling medium is the degree of interactivity. If a game is heavily story-based but I can get all (or most) of the game's value just by watching a youtube video, is there really any benefit to it being a game, as opposed to a movie or TV miniseries or whatever?
Why not just use the game's engine to tell your story and release it as a made-for-youtube movie? Maybe with some clever narration a la the best let's play creators? I have no idea how the margins would be compared to a game, but if your game is going to bomb because everyone gets all the value just by watching some guy record himself playing it, you might as well be that guy.