> The Magit experience is due to the use of the transient package for its UI.

(I'm the author of Magit and Transient. (Though not the original author of Magit.))

The transient menus certainly play an important role but I think other characteristics are equally important.

A few years ago I tried to provide an abstract overview of Magit's "interface concepts": https://emacsair.me/2017/09/01/the-magical-git-interface/. (If it sounds a bit like a sales pitch, that's because it is; I wrote it for the Kickstarter campain.)

This is my experience. While transient mode helped at the beginning for discovery. I learned fast the 10 things I use constantly, and never look the transient buffer. When I want to do something, I see the documentation, for me it is often easier than guessing and searching. Things like spin-off are absolutely gold.