Sidenote:

Here is one version of the DOS event that I found on the net within a minute.
It's words on a page. Who knows what actually happened.

https://cult.honeypot.io/reads/lesson-from-gary-kildall/#:~:text=But%20here's%20what%20Gates%20did,and%20licensed%20it%20to%20IBM.

https://soundcloud.com/sunset-poet-of-texas