One measure is the number of stars on github and active contributors 49.7k vs 25.7k and 737 vs 79. The other measure can be the number of new extensions being written for each of them (particularly extremely high quality ones like telescope). Searching `nvim` on github yields many plugins which are advertising the Neovim editor by having it in their name, some of these are even ones which support vim e.g. Shougo/denite.nvim all of which point to the fact that neovim is a huge success and is on tract to overtake vim. It would not be an exaggeration to say that a lot if this is due to first class lua support in Neovim. By adding nice features like treesitter and LSP it has become an improved version of vim, an editor that actually understands the code being edited beyond simple text objects (e.g. https://youtu.be/E4uaPs9e9UU?t=68)

According to the latest Stack Overflow developer survey, neovim is used by almost as many people as Emacs is[1].

By your own definition, Emacs is a “huge success”, therefore I’d expect you to extend that description to nvim, too.

[1]: https://insights.stackoverflow.com/survey/2021#section-most-...