That's because no one knows their history anymore.

Nano was a (bloated as usual) GNU clone of Pico. Its only reason for existing is GPL freedumb nonsense that was popular back in the day. It copied the UX of Pico.

Pico was not developed as a standalone editor; rather it was the builtin editor for the Pine email reader. Hence the weird keybindings — it followed the UX of the email client.

Pico stood for PIne COmposer.

It became a simple universal editor because vi and emacs sucked and for some reason no one felt it necessary to invent something better.

Users repurposed the editor from a mail client because it was already there. Nearly every university Sun box in the 90s had Pine installed for reading email.

It was written by the same guy that invented IMAP at the University of Washington.

Can't wait for the Rust clone of Nano then the cycle will be complete.