Earlier quoted context omitted.
If we make a distinction between CLI apps and TUI apps, my interpretation is that the article was specifically talking about the latter. By a CLI app (with the emphasis on command line ) I mean something like grep, sort, cp, git, ls, tar, etc. The normal way of interacting with these is by writing commands on the shell, which means that if you know how to use it normally, you can also use it in a script. Which means…
You should not underestimate how confusing those CLI tools are to people who have never used them before. For example, I would argue that for someone with no experience, figuring out how to copy a file from one folder to another is easier in Windows Explorer than learning how to use cp.
I don't believe this.
If you find a person (well, two I guess for this experiment) with no computer experience and want to teach them how to copy files, your first step will be teaching them what is a file and how they are organized in the computer.
Explaining what a file is takes the same amount of time for both cases (we can ignore how devices and processes are files in Linux and how files in Windows contain many data streams and extra metadata).
In both cases you need to teach them the file system is hierarchical and folders can be nested and can contain files.
For Windows you have to teach them how to double click to open folders. They can double click "My Downloads" to see their downloads. They can double click "My Music" to see their music files.
For the CLI you have to teach them that `ls` can list the contents of a directory. They can `ls Downloads` to see their downloads. They can `ls Music` to see their music files.
For Windows you then teach them they can open multiple windows (assuming you want to copy from one folder to another folder). And you teach them they can click, hold and drag and drop a file to move it (but sometimes it will be copied when they do that) and they can hold in Control while dropping to copy the file to the destination instead. Or you teach them they can use Ctrl+C to mark a file for being copied and then navigate to the destination and use Ctrl+V to copy the file. Or you teach them to right click for the right click menu, and that "copy" means "mark this file for being copied", and that a right click in the middle of a window displaying the target folder lets them select "paste" which means "copy the marked file here".
For the CLI you teach them `cp Downloads/foo.mp3 Music/` copies foo.mp3 from their downloads to their music directory.
The CLI is also infinitely easier to help newbies use over the phone!