psql command line with readline

Original query:

Problem: psql (readline) is not groking vi editing mode on the psql command line.
MacOS 10.13.6
$ psql -V
psql (PostgreSQL) 11.1
$ cat .inputrc
set editing-mode vi
set keymap vi-command
$ echo $SHELL $EDITOR
/bin/bash /usr/bin/vim
$ psql