a few weeks ago I did highlight that in Pike's infamous Software Research Is Irrelevant talk that the emacs-centric lisp machines prior to the 90s were not unix(-compatible) and were a casualty of unix in the same way Pike's plan9 was a casualty of unix.
But then, Pike was complaining that in 2000, basically every programmer used emacs on unix and in 1990, basically every programmer also used emacs on unix so maybe there is a special link between emacs and unix.