I use vim, yes I know, it is not cool anymore. I cannot remember why it was vim. But from the two CLI editors that were installed by default in Debian I decided that vim is for me. I assure you I have no clue how nano works.
Actually it was vi. Then I installed vim.
I just followed some lines of the man page and that was it. Later I learned some more commands and tricks and I still do not know them all.
Vim to me is fast, light, efficient, really productive, it is free software right from any official Linux repository and ready to use. Yes, I like that I can use it from the terminal and I do not use any GUI with it.
The second IDE that I have installed because it comes by default in any Xfce distro is Mousepad and sometimes Leafpad. I use them just for some edits when I am already in Thunar but it is rare.
I use vim especially for editing configuration files and scripts, e.g. on Debian and Slackware. I make notes with it and one of the most important files that I edit with vim are my bibliographies. I am a teacher. I also write small texts with it.