The Graphical User Interface – 1945 to 1980
lunduke.substack.com
lunduke.substack.com
I feel like you didn't read it, despite it not being a long article. It stops at 1980, not '80s. Also it covers Sketchpad, Alto, and PERQ (the latter of which I hadn't heard of) in addition to Memex and the Mother of All Demos. It wouldn't make sense to cover 1980s GUIs when the article explicitly ends in 1980. It's obviously not meant to be a comprehensive history but just a taste of pre '80s GUI history.
I think there wasn’t much to show until interactive computing became feasible. The idea of pairing a person and a computer (or time-sharing a computer between multiple users) and provide graphical or direct manipulation interfaces wasn’t there for a long time. IIRC the Linc provided a small CRT that could be controlled by software and kind of beget the PDP-1.