You are mixing apples and oranges. The fact that the GFDL sucks hasYes, GFDL has nothing to do with the main issue. No, it is not necessarily illegal to redistribute binary images of the kernel as they are today (see below). The first problem is that they (the complete w/firmware kernel binary images) are not DFSG-free, anyway. The second problem is that some firmware blobs don't have explicitly stated in the kernel tree which exactly are their licensing terms for redistribution -- those are, in principle, undistributable.
nothing to do with the firmware issue. With the current situation of
firmwares in the kernel, it is illegal to redistribute binary images of
the kernel. Full stop. End of story. Bye bye. Redhat and SuSE may still
be willing to distribute such binary images, but it isn't our problem.
Putting the firmwares outside the kernel makes them distributable. SomeIf putting the firmwares outside the kernel makes *them* distributable, then the binary kernel image is already distributable -- just not DFSG-free. The important fact WRT Debian, IMHO, is that putting the firmwares outside the kernel makes the kernel binary image DFSG-free.
distributions will want to include them, some others not. But the
important point is that it makes that redistribution legal.