> When does widespread ’70s/’80s computing stop being impressive?
When the majority adopts it, or at least knows about it.
> You say “unknown” as if we were talking about some research software, or some old and largely forgotten software. Unix shell programming doesn’t have hipster cred.
It's unknown to those that are only experienced in working in a GUI, which I believe is still the majority of developers. In my experience, anyone of those people are always impressed when seeing me work in my screen filled with terminals, so it does seem to have some "hipster cred". :)