I think we went past each other at some point. I was not arguing that you can use Emacs as a terminal emulator. I was talking more about terminals and shell being a way of computing. Emacs is an alternate way of computing.
With terminals, you have the escapes sequences, the alternate screen, the shell capabilities. With Emacs, you have a lisp VM with a huge library of functions and buffers. I still use a normal terminal like xterm and Terminal.app, but I have eat installed and it's working great.
I agree with you, once you have a terminal emulator like the one described in the post you are close to reinventing eMacs. Many have tried over the years, no one succeeded so far.
With terminals, you have the escapes sequences, the alternate screen, the shell capabilities. With Emacs, you have a lisp VM with a huge library of functions and buffers. I still use a normal terminal like xterm and Terminal.app, but I have eat installed and it's working great.