I still have a BeOS 3.5in floppy in a drawer somewhere, so this announcement produced a little nostalgia for ~1999 or so. That said, it's sort of hard to imagine lots of new OSes springing up, they take a lot of care and feeding... I would think the obvious choice would be to somehow to support packages from another OS (say Snap or Flatpak apps from Linux), so that you could overcome the need to port everything (or have no users).