I highlight the text and middle mouse button for paste.

Didn't you say you liked command-line interfaces, not GUIs?

I'm not sure how using a mouse to select text means that you're using a GUI. I spend most of my working day in an Emacs window, which is ostensibly text, but it doesn't mean that there aren't cases where selecting some text with the mouse is faster than moving the cursor to the text by retyping it. People have been using mice with computers before windowing systems were even invented.

And on a Mac, you do Cmd+C. Neither maintains uniformity.

On macOS, it's very simple, consistent, and intuitive:

GUI menu shortcuts are invoked with Cmd, and that includes copy/paste.

CLI shortcuts work as always (and there's no overlap, because of the extra Cmd key).

ctrl-C not command-c to exit a process.