Back in the late 1990s, I read an article in some computing magazine where the author argued that command line is more intuitive than a GUI. Their main evidence was a simple experiment. They sat a number of computer illiterate people (presumably those were found more easily in those early days) in front of computers running DOS and Windows and asked them to delete a file. Facing a blank screen with a ">" prompt and a keyboard, most of them eventually figured out the "delete" command. It was less obvious to make a connection between the mysterious gizmo next to the keyboard with a wire hanging from it and an arrow on the screen, and even less so between that and how to use that to delete a file.

IMO that experiment is seriously flawed. Computer illiterate people would have no concept of what a "file" is, let alone how to "delete" it. It would definitely not be their first concern when learning how to use a computer. GUIs have been a tremendous boost, helping countless millions to enter the world of computing, as history has clearly shown. In fact it was the keyboard that has all but disappeared.

Having said that, "just press buttons and see what happens" does not always lead to the nirvana either. I still have not figured out how to do what I consider basic things in image processing, for example make one image transparent and overly it on top another, let's say rotated by 15° for a good measure. I know how to do it in some applications but only because I am quite experienced in those. The next time I sat in front of an unfamiliar application and tried "randomly pressing buttons to see what happens", I ended up giving up in frustration.