Over the years I've used a lot of editors on unix shell; ed, jed, joe, pico, nano, emacs, vi(m) and I think vim is the best editor on shell for its performance, speed, and mobility. It's a rational choice for SRE/DevOps type engineers. I still sometimes use nano for very quick edits especially when having no physical Esc button frustrates me. However if mobility is not a concern, in other words if I'm editing files on my own environment (say my mac), I'm running Emacs.