Those shells still inherits genes from the terminal era where metacircularity wasn't affordable. Emacs got a free meal from lisp so it can inspect itself and suggest to the user even in command line style.
Recent shells have done good efforts to provides some kind of typing and deduction to reduce friction. It's always nice to have a listing of /etc/hosts or ssh known hosts in place. Browsers picked this since the coming of 'smart' url-bars.
I hope one day we would go all-alan-kay on this and simply have a meta-capable system that parse/cache relevant data straight from the source so you don't need to do any extra work to make the system understand a bit your additions.
Recent shells have done good efforts to provides some kind of typing and deduction to reduce friction. It's always nice to have a listing of /etc/hosts or ssh known hosts in place. Browsers picked this since the coming of 'smart' url-bars.
I hope one day we would go all-alan-kay on this and simply have a meta-capable system that parse/cache relevant data straight from the source so you don't need to do any extra work to make the system understand a bit your additions.