Dennis Ritchie used and Russ Cox and Rob Pike use acme.
Ken Thompson, Bjarne Stroustrup, Doug McIllroy, Tom Duff and Brian Kernighan use sam.
What editors do other famous programmers use? Do other famous programmers also use mouse-based editors like sam and acme? What other editors are used by famous programmers?
Why do so many Hacker News readers have such an aversion to using the mouse when editing if these luminaries of computing have all moved on to mouse-based editors?
Because most of the HN readers (those who are programmers, anyway) are down-in-the-trenches programmers, and as such, they choose whatever editor/environment makes it the easiest to edit source code. If it is Vim, it is Vim then. If it is Emacs, Emacs it is. Nano, Elvis, ed, Sublime Text, LibreOffice Writer, Inkscape, Gimp -- whatever helps to write. It's the code that is published on SvnHub or whatever, after all, not the environment's settings.