Pfft, I'll be impressed when Emacs runs as pid 1, has an inittab.el, mounts filesystems, sets up swap, starts daemons, launches X, reaps zombines, and deals with shutdown. I'm sort of surprised nobody's done that yet.
Try Guix System. The entire system, including PID 1, is configured in Scheme (Guile) and has a very nice Emacs-like hackability.
That's old news: https://web.archive.org/web/20190118221826/https://www.infor...
Fwiw I use EXWM in Guix and only interact with the computer through emacs (though I do need to use terminal and eshell).
Handling SIGCHLD and doing the right thing is table-stakes for a functioning init, IMHO. This isn't that.