I think your splitting hairs on this one. The Micral N also didn't have a GUI environment and it was clearly destined for the top of someone's desk. In my opinion that makes it a desktop computer.[0]
When Alan Kay was working on GUI environments, it was on equipment that pretty much nobody could access, it was very expensive and few units were sold. Still, it's interesting to note that the Altair was not a desktop computer that could literally sit on a desk: it came in a cabinet that was meant to sit on the floor.[1] ;-) The irony!
When Apple released the Macintosh, I believe most people were interacting with desktop computers that lacked a GUI desktop environment. Specifically I was thinking of the IBM PC XT [2], although, as you note, there was more to the field than just that.
When Alan Kay was working on GUI environments, it was on equipment that pretty much nobody could access, it was very expensive and few units were sold. Still, it's interesting to note that the Altair was not a desktop computer that could literally sit on a desk: it came in a cabinet that was meant to sit on the floor.[1] ;-) The irony!
When Apple released the Macintosh, I believe most people were interacting with desktop computers that lacked a GUI desktop environment. Specifically I was thinking of the IBM PC XT [2], although, as you note, there was more to the field than just that.
[0]: https://en.wikipedia.org/wiki/Micral
[1]: https://en.wikipedia.org/wiki/Xerox_Alto
[2]: https://en.wikipedia.org/wiki/IBM_Personal_Computer_XT