Cannot be played under Windows 8 with AMD graphics.

AMD is currently supporting Windows 7 and Windows 10. They haven't released updates for Windows 8 since 2017.

The old AMD drivers for Windows 8 do not support newer features of Vulkan. NMS needs these features and won't work on Windows 8 and AMD GPUs. That said, if you want to keep Windows 8, you may be able to use the Windows 7 drivers if you are willing to go that route.

I'd asked GOG to update the "other:" entry in the requirements section, but GOG understandably only wants to mirror what the game make says. However, HelloGames hasn't updated their requirements page since sometime before the switch from OpenGL to Vulkan. (I sent them a note, just before posting here.)

Just curious, why are you still using W8?

Because windows updates have generally been worse than their previous versions (bloatware/messy multiple layouts) since forever. A clue if you want, it was called "windows", not "Panes with stuff in random moving places"