The problem with the cli is you need to memorize a whole bunch of new words and syntax in order to do anything. You also need to memorize what not to do so you don't accidentally erase your system while using rm or cp or whatever.
Even something as simple as copying and pasting, which works the same in every single other program has new rules in the terminal. I mean, think about that. If you're just learning bash, then the first thing you'll be doing is copy pasting commands. But even that has the hurdle of 'oh, I guess this is the one program where ctrl-c means something else
Like, how do you look at sudo, cat, man, and apt, and think 'yeah that's intuitive'. And forget about multitasking, new users won't even know how to quit most programs (is it ctrl-q? Just q? Esc? Ctrl-c? Ctrl-d? Wait how do I undo that, is it ctrl-z? Wait where did the thing go
(it can't)