Hussar
Legend
When you logically critique a definition, single examples that argue against the definition are revealing. However, I'm not doing this, I'm questioning the very premise you're starting with. Defining RPGs by the creation aspect isn't valid -- there are many games where creation is critical to play, Pictionary being a useful example. Nothing in Pictionary tells me what to draw, only what I need to get my teammates to guess to win a point. This is closely analogous to setting a scene in an RPG -- I create this to get the players to engage with it using the rules to achieve the goal of play. Again, you're method focused, which is going to fail for you because you seem to have a huge blind-spot to non-D&D, non-DM-centric RPGs and how they function (which can be wildly different from D&D). For instance, no myth games are predicated on the premise that nothing is made up outside of play -- all facts for the game are presented by the players during play and become the setting, not the other way around. The players literally create the setting in play via their action declarations.
Instead, you should look to goals of play -- outcomes. There's a pretty general definition of the goals of RPGs, and it differs from other games to a useful degree.
But, Pictionary DOES tell you to draw a picture. You cannot do anything other than draw a picture. Granted, the picture you draw is up to you, but, again, the game is directly telling you what to do, even if it doesn't tell you how. In creating a scenario, the RPG game does not tell you what to create, other than "create a scenario" which is so broad and vague that it literally can mean anything. I reject [MENTION=23751]Maxperson[/MENTION]'s equivalence that all set-up is the same. The fact that you have to step outside of the game in order to create the scenario is a major distinction.
Even in a no-myth game, you MUST create something before you can play it out. Granted, it's mashed up in play, but, it's still a clear causal line - material is created, that material is then played out then more material is created, then that material is played out, wash, rinse, repeat. There is no real difference here - the creation must come first, the stuff that is created is not dictated by the game itself and play is then shaped by that material that is created, which is not actually part of the rules of the game.
Again, you're focusing on the timing. That's not the point. The point is, the material that must be created in order to actually play the RPG isn't created through the RPG itself. It's added onto the RPG and then played out and, until it's created, you simply cannot play at all. If I decide there's a hammer in the shed that I can use to fight the zombies that are chasing me, I'm creating the fiction first and then playing out that scenario - fighting the zombies with that hammer. The in-game fact that there is a hammer in that shed is not created by referencing any rules of the RPG. It's something I've drawn from the outside to add in and I have to add it in before I can progress forward. If I do not add it in, play cannot progress down that line.