Oh and if you're lucky you have the option to hover for a second to find what the icons mean through a tooltip. Having to do that with every icon until you find the right one is not pleasant.
I just find typing "help" or "man" a lot more intuitive than the random clicking on icons.
I'm sure that I'm a rare specimen and most people would prefer clicking to reading, but personally I find discoverability a bad user experience.
Having a row of icons with vague meanings, or endlessly nested/badly categories menus isn't intuitive or easy.
Conversely, there are a plethora of terminal-based programs with absolutely excellent UX.
Anyone can edit a well-documented template/example config file, and a good CLI program is almost like an interactive conversation, which again is an extremely intuitive experience. It's not the fault of whether the interface is graphical or not in most cases, it's just mediocre/bad software.