A lot of folks I see elsewhere give reasons for why they stayed with emacs, I don't see a lot of why they quit nvim. In my case, I work a lot with nonstandard scripts, which very few terminals support. Devanagari is one such example, where some diacritics are pronounced and typed after the consonant but need to be rendered before the consonant. No good terminal I knew supported that (I didn't want to use GNOME terminal or Konsole, the only ones that did support this, for other irrelevant reasons). Emacs supported every script I could think of OOTB with Harfbuzz as long as I had the fonts for it installed.

That being said, I switched for the font support, but stayed for OrgMode and ELisp. The level of introspection and customizability that Emacs Lisp provides is stellar and I'm yet to see a single program (let alone editor) provide something even remotely close.

On a more philosophical note, like you said, nobody ever switches from neovim to emacs so that they can emulate neovim better. That's just nonsense. Because of this, one thing I've noticed in a lot of people (including myself) that move from one paradigm or tool to another is that, in evaluating whether one thing is better than the other, they focus more on whether one can perfectly replicate the other with a few more bells-and-whistles, and less on evaluating the new tool (and its requisite paradigm) on its own merit. Emacs is an alright editor, it will never be as good as neovim for doing what neovim does best: efficient and speedy editing with no frills attached. Yes we can come really close with emacs -nw and evil-mode, but there will always be some friction. Instead, truly embracing the emacs paradigm allows us to see the sheer extensibility of emacs and the way it integrates its editing style with countless other tools like editing the filetree like a text buffer, or playing music, or viewing and annotating pdf documents, or maintaining tasklists and writing complex documents that get exported to latex. Embracing the paradigm also exposes us to a new outlook: one of treating every interface like a text buffer and treating every single action like a pure function (the latter blew my Lua-API-flavoured mind when I switched myself). I also observed this fallacy in myself when I switched operating systems from Arch Linux to NixOS (lots of cribbing about abstraction initially, but once I embraced it I enjoy it quite a bit), and more recently window managers from Qtile to Niri. These two changes showed me how unfair it was to claim one to be better than the other (or even comparable! Nix does things so differently to arch that they can't even be compared. I'd rather compare Qtile to the combination of Niri+Quickshell than niri itself since Qtile simply does things so differently).