> The Hurd is GNU's replacement for Unix, not a research project.
Well, it certainly started out as a intended Unix replacement to complete the GNU ecosystem since a GPLed kernel was the last missing piece. But looking at its history and detours with the attempted replacement of Mach with L4 and Coyotos I think they definitely strayed into the research space. It was probably never intended that way, but things tend to change a bit over 20 years :).
> Research OSs may not go anywhere in most cases, however that does not make OSs that are not going anywhere research OSs.
Yep. I still think it applies to both the current Hurd as well as Minix 3.0 to some extend, but the discussion about what is a research OS and what not is about as decisive as talking about hybrid kernels (see [1]), i.e. the NT as well as OSX kernels are prime example where nebulous claims just cloud up the whole discussion.