What you're both sneaking up on is a standard kernel API for
graphics, so that it has all the information about the state of the
FB/GPU, [...]
That's not how I read it.
The kernel has information about FB/GPU state, but only enough so that
it can draw text on the console (or know that it can't and thus avoid
trying). This is a far cry from an "API for graphics", which to me
means something that all graphics-drawing programs must use to draw
graphics. The proposed paradigm, AIUI, is something that does not
concern a program that draws but does not chnage the video modes.
Naturally, this means excluding X11 (and everything else in userland)
from whacking the hardware directly, while simultaneously exposing
all of the functionality of any given GPU behind a properly
authenticated/protected interface.
The interface you're imagining does. The interface proposed (again,
AIUI) does not. Rather, anything is allowed to whack the hardware
directly, but if that whackage includes changing the video mode, it
must tell the kernel about it, so the kernel can adjust its idea of how
to draw text on the console appropriately (or realize it doesn't know
how to and thus avoid trying).