I share your wish. Emacs, as wonderful as it is, has accumulated a lot of cruft over the decades and would benefit immensely from a rewrite. A "Neo-Emacs" could be multithreaded from the ground up and drop support for archaic platforms. The rewrite could even be in Rust to attract younger developers.
>a lot of cruft
Like what? Emacs is written in C and there are ports of it out there (all half-abandoned). Emacs, the way it exists, works very well.
There would be no point to writing emacs in a language that can’t be developed interactively in a repl. Emacs being written in lisp is an essential quality.