I think you’re missing quite a few like:

• z/OS it’s IBM’s mainframe OS, so super corporate and niche
• raspberry pi os should be included because it’s pretty mainstream
• android and iOS should be on there because they’re very mainstream, not technically desktop OSs but for a normie with a tablet what’s the difference?
• there’s a lot of embedded OSs that could be added (open WRT, Windows IoT, NetBSD)
• no Temple OS?
• free DOS?
• Whatever special ones they use for super mission critical stuff like the ISS