You are taking the "expression" too far. We are talking about expression at the time of doing, not at the by-product of doing. GUI constrains you, it limits your expressive ability to tell the computer what to do. CLI is extremely expressive, it allows you to tell the computer what to do in very elaborate way, not only by having more options available for each command, but also by allowing you to combine things in ways GUIs simply can't allow for.
We are not talking about end products of this communication between computer and person, its output which could be images or software you created with the computer and which also allow you to express yourself in the more broader sense.
I'm not the grandparent, but I use TikZ to "programmatically" create graphics in LaTeX. It is much faster and looks much better than what I produce in the GIMP. (See e.g. http://www.texample.net/tikz/examples/.)
Of course, I'm drawing graphs and geometric objects, not trying to do "photo work" - but CLIs can be an excellent interface to some kinds of graphics.
No, I'm not. If you read carefully you will note that I'm talking about your expressive ability to tell the computer what you want it to do. Not about your ability to express yourself through a medium like video or images.
By the way, there are some great CLI tools (like ImageMagic) to manipulate images from the CLI and these are indispensable for batch editing large collection of images and other applications (image analysis), but I was not referring to that.
Ok so I want to select the pretty green color from a photo for future use. In MS paint it would be two actions select the color selection tool and select the color. How do you do that from the CLI in more expressive way?
Why should you be able to "select the pretty green color from a photo" via the CLI?
That's my point - just because it's the wrong tool for some hyperspecific job doesn't imply anything useful in general.
But if you really want to pursue the analogy, we could in fact come up with a command line that selects the green color value from a certain area of an image a lot easier than one could edit a non-image file using MS Paint (though I've seen that done too).
I think GUIs and CLIs can both be "valuable tools for expression".
But Photoshop is an example of something that's particularly good for the GUI. It's not representative of most things that people do when they're interacting with a computer.
The main thrust of the article is that CLIs are expressive, and GUIs are not. I came up with a counter example QED.
He pushes this topic by talking about Unboundedness vs Boundedness and Internalization vs externalization. What he seems to fail to realize is that internalization and unboundness are not properties inherent to CLIs nor is externalization and Boundedness inherent to GUIs. Those properties are a function of how you designed your application and user interaction not the medium by which it is accomplished.
The discussion is getting nowhere because the author is not even wrong. He's conflating too many things and picking analogies that sound correct but don't make any sense once you dig deeper.
We are not talking about end products of this communication between computer and person, its output which could be images or software you created with the computer and which also allow you to express yourself in the more broader sense.