The DOM definitely has its problems, mind you. Investing some time in designing a proper replacement for it is worth it, as long as people understand going in that the project might well fail.
The ones I've seen are actually faster -- Flipboard for one gets to 60fps scrolling on mobile, IIRC. And of course all WebGL based interfaces on native mobile apps that re-implement parts of Cocoa Touch et al, are not that shabby either.
Sure, it doesn't have as much accesibility, but that's something that can be fixed in the future (and of course people needing more accessibility can always use more conservative alternatives).
People have tried to replace things like text editing (with canvas-based editors), CSS layout of the DOM (with various JS solutions involving absolute positioning), native MathML support (MathJax; this one has of necessity done better than most, because of so many browsers not having native MathML support). There are a bunch of things out there that attempt to replace or augment the built-in form controls, with varying degrees of success.
https://github.com/domokit/mojo/tree/master/sky https://github.com/domokit/mojo/tree/master/sky/specs
None of the projects that you mention are really relevant to the discussion. I agree that they didn't change shit but it's precisely because they are still built on the DOM and cannot really go below that in the abstraction layer.
There exist UIs done in Canvas and WebGL that are arguably below the DOM in the "abstraction layer" and don't need to use much more DOM nodes besides opening a canvas/gl panel...
(Most full screen 2G/3G web games fall into this, for starters, and those are in the tens of thousands. But there are also lotsa apps).
Increasinly high end apps do.