Unmaintained.
The upstream libsass library was declared deprecated on 27th October 2020:
Warning: LibSass is deprecated. While it will continue to receive maintenance releases indefinitely, there are no plans to add additional features or compatibility with any new CSS or Sass features.
This would effectively mean that lua-sass is also deprecated, but in addition to that, since I no longer have any need for (or interest in) Sass, I now consider lua-sass to be entirely unmaintained.