IMHO, that's missing out the relevant bit. RPN and stack juggling is a red herring. Being able to bootstrap the system from zero and then turn it into anything

IMHO, that's missing out the relevant bit. RPN and stack juggling is a red herring. Being able to bootstrap the system from zero and then turn it into anything is the real distinguishing feature of Forth. The only other language that can do it is Lisp, but Lisp assumes dynamic memory allocation to be the most fundamental operation while Forth doesn't.