Emacs - the editor that STILL doesn't have a simple way to duplicate the current line?

I think the germane point about Emacs here is that some people like writing Lisp and some people hate it. If you hate it Emacs is likely not going to be your best environment, and that’s fine.

I really like writing Lisp so Emacs has a simple way of doing anything I want, but it’s not for everyone.

I think this is a larger problem with Emacs. Duplicating a line is something that should be easy to do out of the box.

And if it's a situation where you really need to make the user define a keyboard shortcut, don't make them do C-c followed by the actual shortcut, let them define single keystroke shortcuts to do what they want. Multiple keystroke shortcuts are so damn annoying.