Something feels a bit off about this story. At the end, the customer is said to exclaim - oh my god, that was Bill Gates!
At the end of 1989, Microsoft was not as famous as it later became.
MS/DOS was just one of several competing DOSs in a much smaller market. And DOS was their main product.
I doubt that even amongst most MS customers there'd have been name recognition for Bill Gates, let alone such reverence.
In 1987 he became the youngest person to become a billionaire, in 1990 he was the 29th richest person in the world. Those were definitely news stories.
I don't have any particular reason to believe the story as it is told, but I am not sure that is a reason to disbelieve it either.
What other DOSs? I know of DR-DOS, but not any others. Also, not sure, but I think MS-DOS was the biggest from pretty soon after it was created. I'm not even sure that DOS was their main product (though it was a big one). I had read the book Le Noveaux Magiciens, about Microsoft, and though I don't remember the chronology now, IIRC, language products were also big for them, like BASICs for various platforms. They even had an MS-C (used it for a product) and MS-Pascal and MS-Lisp. Could be wrong about languages being big earners for them, though.
I recall Amstrad in UK had its own DOS in the early 1990s. They had to declare MS compatibility, which supports your view of MS already being dominant.
I also don't remember much before 1989, but I believe the languages business was earlier and more niche. Ever read Gates' 1976 rant about hobbyists ripping him off?
I remember my PC-1512 (XT clone with 512 Kb RAM, two 5.25" floppies and a mono CGA monitor) and it came with MS-DOS 3.x and DR-DOS boot floppies and also included the GEM window manager. I believe the version of DR-DOS used could also run CP/M 86 executables as well as normal DOS programs.
Yes, I had read his rant, I think it was originally to members of the Homebrew Computer Club, maybe paraphrased, in Steven Levy's book "Hackers: Heroes of the Computer Revolution", some years ago. Pretty interesting book, though I guess Levy may have hyped it up some for sales. Still remember about (Peter?) Deutsch, a lot of stuff about GNU, Lisp and Emacs development (some of the most interesting parts of the book), milliblatts, TECO and many other topics .... :)
And my favorite slogan of all from the book, "Tools to make tools" :)
There were other DOSs, but even by 1989 the use of unqualified "DOS" was usually taken to mean "IBM-compatible PC running MS-DOS" (eg. "Our school has both Apple and DOS computers in the library").
No. Microsoft had more than just MS DOS, ex. MS Word for DOS, which competed head-to-head against Wordperfect. You forget that the PC craze was well on its way by 1989, and Microsoft had their IPO 3 years previous, so obviously Bill Gates was known by many at that point because he was already a billionaire, and very young.
Sure, Bill Gates was even more famous later on, and Microsoft was even more of a dominating factor in the 90s, but he wasn't chump change in 1989 in the least.
At the end of 1989, Microsoft was not as famous as it later became. MS/DOS was just one of several competing DOSs in a much smaller market. And DOS was their main product.
I doubt that even amongst most MS customers there'd have been name recognition for Bill Gates, let alone such reverence.