I don't think that helps support the argument, though. Despite using a stylus-driven touchscreen, the Palm Pilot UI had a lot more in common with the desktop UIs of the 90s than with today's smartphone UIs or even today's smartphone-tainted desktop UIs.
withinboredom|10 days ago
wtallis|10 days ago
Meanwhile, the rest of the Palm Pilot UI (all the parts that were actually on the screen instead of below it in the dedicated writing area) looks thoroughly 90s: the basic buttons, drop-down boxes, tabs and dialog box layouts, scrollbars that aren't trying to hide from you. The main UI elements missing from the Palm Pilot that were present in eg. 90s Mac OS or Windows are the free form desktop layout (instead of the smartphone-like app launcher grid), and the persistent on-screen menu bar or taskbar.
The Palm Pilot UI was unquestionably designed around the assumption of higher precision than today's touch-oriented UIs. The stylus was not considered optional. The lack of capacitive touch sensing for gesture recognition meant the UI was much more reliant on precise button taps where today's smartphones would use swipes and other gestures for stuff like scrolling or "back".