I think you're running together two different things.Off on a tangent here, but is this what is called narrative games in The Forge's Narrative-Storytelling-Gamist theory? I must admit I never quite grasped the concept of narrative as they use it, but this seems pretty close.
Narrativism is, in the Forge's lexicon, a species of motivation/aspiration for RPGing. Roughly, it is RPGing with the goal of having an aesthetically pleasing and significant experience by participating in the creation of a story. A contrast is intended with White Wolf or AD&D 2nd ed or AP-style "storytelling", in which the story has already been authored, and so the players don't get to write it but only to get to learn what has been written.
Narrativist play depends upon techniques that avoid the GM having already written the story and deciding what is significant and what isn't. One technique that is popular for this is "scene-framing": rather than the GM preauthoring a setting which the players then explore via their PCs, the GM frames the players (via their PCs) into circumstances of dramatic conflict/challenge - using, as cues for this, information provided to the GM in various formal and informal ways by the players. The resolution of each scene provides the material (new shared fiction, changes in PCs' dramatic needs, emotional/thematic elements, etc) out of which new scenes are framed.
I'm wondering which no-myth/scene-framing systems you have in mind.In both the sandbox and the adventure path you have tons of 'myth'. That is to say, on the slice of possibilities we are discussing the notion that that there is a concrete setting preexisting the players is largely assumed. The idea is do away with the setting, which in theory allows you to produce stories with lots of play buy in, but without fixed goals or events because the setting itself isn't fixed and is generated in response to player proactivity. It sounds good in theory, but in practice it has a lot of huge traps. One of them is that when you do away with a concrete setting, you remove the one security that the players have that they characters actually have agency. Theoretically, if the players are being allowed to create the myth based on their metagame desires, then the players have agency. But if the GM is not being constrained by his prior agreed upon myth, the problem is the GM is not being constrained at all. The myth that a GM creates for himself and his commitment to stay true to that myth is the one real limit on GM power. How can you say you overturning the GM's 'will' for the game, if the GM is completely free to create any contingency that they want?
In fact, what 'no myth' games seem to do is get players to accept buying a ticket on a railroad, and then letting the GM railroad however he likes. They even openly promote railroading techniques as ways to improve the story, with the GM empowered to create whatever he wants at any moment to have the story move in the direction the GM at that moment thinks will be best. If the GM wants the bad guy to escape because it's good for the story - a classic sign of railroading - in these games that's what he's supposed to do.
The systems of this sort that I'm familiar with use a range of techniques to constrain GM power - mostly tight action resolution mechanics, but also mechanics that allow the players to engage in various forms of director-stance-ish fictional content introduction. And sometime also constraints around GM fictional content introduction (eg the Doom Pool in MHRP).
Your example of having the villain escape, for instance, involves the GM suspending the action resolution rules. I'm not sure what Forge-y system you have in mind that advocates this. I typically associate it with the WW "golden rule", which is exactly the sort of GM pre-authorship that Forge-y narrativism is trying to avoid.