Earlier quoted context omitted.
The Plan 9 UI is deeply arcane. It's heavily inspired by the Oberon UI, which itself is equally arcane, if not even more so. I have a play with Inferno in a VM some years ago. (I can't even find an ISO of it now, which is something that needs fixing badly, alongside a ready-to-run version for Linux on x86-64.) Oberon, and thus Plan 9, spring directly from the era of the original Xerox PARC Alto. Their design comes fr…
Only acme mimics Oberon. The rest is inspired only, as you said, by the original smalltalk GUI.
That is a good point, true.