They are also much more interaction based than people typically ack. Ctrl-z sending something to the background and being able to list the currently active job

They are also much more interaction based than people typically ack. Ctrl-z sending something to the background and being able to list the currently active jobs for the current shell are specifically affordances for someone sitting at the keyboard. Even the pushd/popd workflow is again for the operator. Python and a few others such as LISP, smalltalk, etc., have some affordances made for a developer at the keyboard. Oddly, most of them are not taught to developers, it seems. The number of people I have worked with that didn't know of python's `help` is stark.