It’s a step in the right direction, and something I’m personally looking into for a project later with other things, but it’s only that it reduces memory usage a lot. The actual performance still isn’t up there, in fact what they get in the paper is just plain horrible.
Voxel cone tracing as a general solution may work one day, and may already be working, on the PS4 only, for really tight corridor environments, in Capcom’s upcoming “Deep Down” But right now as a general solution it’s not workable, at least in a power envelope where you could run an entire rest of a game on a reasonable set of platforms.
The deep g-buffers thing is another completely useless idea, anything screenspace for “global” illumination, no matter how many hacks you throw at it, is not the way to go. Temporal stability of global illumination is pretty much the entire idea of “Global” illumination to begin with.