What is your definition of "running an OS properly"?
For what?
I need an OS to do my daily work. Since this daily work is doing QS on a Windows application written in C#, nothing other than Windows 10+ will do, period.
I need an OS to do some occassional gaming. That will require a working Steam client. Windows and Linux are an option, other OS's are not, period.
For my PDCLib project, an OS needs to have a C compiler, and the necessary support needed for hosting a C library -- file system (open / search / read / write / close / delete / rename), memory management (allocate / free), a clock if you want to have meaningful <time.h> support, and threads if you want <threads.h>.
I have plenty to do yet on that project before I can start porting it to [whatever] platform, and since Amiga is where my heart is, that one will be the first non-mainstream platform I will
personally port to. I would not be interested in working on levels below that (e.g. implementing basic file system functionality or the threads system myself), but I'd be happy to (help to) port my C lib on to a system that doesn't have one yet.
For that, I'd consider minimum requirements to be...
- some kind of terminal,
- some way to edit - compile - run on that terminal, or a cross-compile / file transfer setup.