It was actually started in 2000 and doesn't seem to have progressed since 2014: https://emacsninja.com/posts/state-of-emacs-lisp-on-guile.ht...
Plus, even if it's finished, will it get any traction in the ecosystem? Will the ecosystem start moving to it to take advantage of its unique benefits? Who knows?
Bonus: Have you heard of GNU Hurd? :-)
Assuming it gets "finished" (is any software ever finished?), it should be no-brainer as long as it provides backward compatibility with old elisp code. And open up the emacs ecosystem to Scheme and Javascript, which could make it much more attractive to newcomers. But, as they say, I'll believe it when I see it.
The trouble with Hurd, IMHO, is that I've run out of jokes. We used to joke that it would run Duke Nukem Forever out of the box, but that one actually got finished. Then it was Perl 6, but that has arrived, too. Star Citizen maybe?
FWIW, when I hear people talk about VS Code, they appear to like it very much. But AFAICT, it has some way to go to catch up with all the functionality emacs has accreted over 30+ years.
Also, there is an effort replace the old lisp engine inside emacs with GNU Guile, which is a JIT compiler that supports Scheme, ELisp, and Javascript. I have not tried it so far, but it might become possible to customize and extend emacs with Javascript in the not-so-distant future.