Love it or hate it, Tokyo Jungle has a lot of what modern counsels need to do. It’s execution as a game is lacking, but the elements are there. It’s short, downloadable, fulfilling, and it’s cheap. That’s basically what people want. Content is only valuable if it’s enjoyable. I can’t imagine anyone really enjoys collecting all the cars in LA Noire or doing all the side-quests in Red Dead Redemption. But you will if you want that trophy.
Here you’ll play until you feel you’re done. When you’ve seen everything you need, you can walk away without feeling bad about it. It mixes brevity with an open ended world, and people will extend that to whatever amount is right for them.