WP for DOS does one thing that justifies its continued existence: the output file contains EXACTLY the text and formatting codes you asked for, and nothing else, every single time. For pre-press document transfer, that was gold. Older versions of Office tended to spit out garbled nightmare with floating tags and text strings that didn't get properly culled during a formatting change or text edit, and from what I understand, a publication created in Word basically had to be saved as plain text and then manually reformatted in another typesetter.
AFAIK that's not such a big deal anymore, especially now that Office saves into some semblance of a proper markup language, and the publications world is half overrun with digital distribution and print-on-demand. But it was still a big deal 10+ years ago and the holdouts haven't all retired or died yet.
He who laughs last, laughs first next time.