For me what I found was that on early 90s telnet-accessible Unix systems the only pre-installed or easily installed editor that actually let me use... luxuries... like arrow keys and backspace was emacs. Vi was always there but modal editing repulses me and it also didn't work with arrow keys and the like. (I've never understood the fixation with avoiding them in favour of repurposing letter keys, something that is just a holdover from the very anemic terminal keyboard that vi was first developed on.)

Emacs was literally the sanest option unless you could bribe the sysadmin into installing "joe" or similar. ("pico" and "nano" came later).

The other thing is back in the day emacs was often a good option for running clients to connect to things like IRC or MUDs or MOOs, and even Gopher and the early web. It was also an excellent news and mail reader!

And so I used emacs as a general text editor and MOO and IRC client long before I ever used it for writing source code really (for which it was also obviously very good).