I think the FSF position comes to down to 1. It's what they've always done and 2. They don't want to be distributing any nonfree software, even when it wouldn't become part of the Free environment
Whereas having a background in embedded design, I can't ignore that I have many more devices running nonfree software than Free software, despite trying to use Free software wherever I can. In particular, my fully Free desktop relies on non-free { monitor, monitor remote, keyboard, mouse, USB hubs, USB hub PS (power supply), USB switch, UPS, network power switch, circuit breaker, ethernet switch, ethernet switch PS, GPON terminal, GPON PS, nonfree BIOS on router }, in addition to the contentious non-free { video card, network card, CPU }. Any and all of those things could be replaced with a Free equivalent, but at the cost of attention that would be better spent elsewhere. In a world being eaten by software, the best we can do is hope for well-defined interfaces with nonfree systems, for our Free systems to interoperate with.
Perhaps a good way forward would be to split (Nonguix, Debian non-free, etc) into two separate categories depending on whether a package runs in the main security domain (drivers, system software, utilities/applications), or is to be loaded into an auxiliary processor (firmware blobs). Then after this distinction became widely accepted, the Free-first distros would hopefully become more comfortable including the firmware blobs, making a better user experience for their Free environments without impinging upon the freedom within.
(FWIW your steelman isn't it - it would seem to indicate that buying a computer with MS Windows preloaded is good from a software freedom perspective)