From the late 1980s until the mid-2000s GUIs had all kinds of standardized visual cues, context sensitive help, UIs usable by both mouse and keyboard, standard interface designs across apps, data binding, and most of all WYSIWYG GUI design software that worked exceptionally well. We had this on 80286 CPUs with 1MiB of RAM and similarly tiny machines.
Today's desktop UIs are a fucking disaster on both the developer side and the user side.
For developers you have a choice between a hypertext language hacked endlessly into a UI and native UI tooling that's far less intuitive and much uglier than what we had back then. Compare the UI designer (not the language) in Visual Basic in the 1990s to today. You could not only design but data bind a complex app that looked decent in 30 minutes.
For users you have no consistency, no keyboard shortcuts (or different ones for every app), no help or help that only works online, etc.