I don't think basic vim usage (which is all I know, really) makes anyone super efficient. I don't think typing/editing speed is generally an important factor in programmer productivity or 'coding speed'.
It's just that every time I use nano it's (a) unintentional, as it's opened via EDITOR; (b) sort-of coerced, because most distros installing it by default also think it's somehow too much to install Vim or Emacs alongside it; and (c) extremely painfully awkward, because all other editors I use, I've invested at least as couple years of practice into.
If I spent a year using nano every day, and if I evolved a config file and read the manual during that time, I might eventually reach a place where using nano didn't feel cumbersome and irritating, but why would I do that if I already use Emacs and Vim every day? If I learn a 'new' editor it's going to be something extensible that I could see myself programming in every day: Emacs without evil; or one of the newer modal editors with a reversed sentence order, like kakoune and Helix; or, hell, VSCode.
So nano is likely doomed to remain forever cumbersome and irritating for me, somewhere on the level of typing on a touchscreen instead of a real keyboard.
