[coldtea]

>GUI interactions aren't composable and extensible the way shell commands are

They might not be in word, but they absolutely can be, and in fact are a superset of CLI interactions (since a GUI interaction step in e.g. Automator can invoke any shell command).

>so you're limited to the features the GUI designer thought of

And in the traditional shell pipeline (that is, not Powershell) I'm limited to working on dumb streams from one command to another.