Lost in Userspace
WordStar died when IBM put the Caps Lock key where the Ctrl key used to be, next to A. Later, Microsoft introduced Word and a generation of bleeding edge WordStar typists were swept out to sea by the Seattle tsunami. That, and your average luser couldn't patch the WordStar customization area to do CUPS ("cursor position") with common VT100 terminal emulations like xterm or gnome-terminal — the escape sequences don't fit in available space for line or column greater than "10" (i.e., 0x31 0x30 is one too many bytes). When WordStar was hot, a lot of conventional computer behaviors hadn't standardized on "user friendly" yet. When that happened, WordStar 3.0 dropped through the trapdoor.
Emacs may be the last surviving dedicated "text editor" from those days, but few learn it, except perhaps for perversity's sake‡, despite a phenomenal feature set. Echoes of WordStar's "Non-Document Mode," useful for programmers, survive in notepads and programmer's editors abounding still — my favorites were UnderWare's Brief and PFE. On Linux, my choices are gedit, Geany and (sometimes) Code::Blocks IDE.
Of course, the only practical document processor these days is Sun Microsystems' Open Office suite. Sun was bought by Oracle, though, so I guess now it's Oracle's. Plus ça change, plus c’est la même chose.
†"Irregardless." Yegods, I love that word!
‡Perverse, as in, you "extend" Emacs by programming in Lisp!