AI or not, I refuse to believe anyone is capable of being the sole maintainer of 100+ anything while preserving any kind of quality. Most of these packages were probably functionally abandoned already, if not technically.
He/She was maintainer of the Void Linux packages, that is the package build scripts, updates, etc., not the projects and source code which these packages are based on.
For example, Guix has now over 32000 packages, including an Emacs package. But of course, they did not re-create Emacs to make that package - they just made a build definition which uses the Emacs git repo, in order to build the Guix package. Or in the case of Ubuntu, it is based on the package definitions in Debian testing, so the Ubuntu maintainers do not have to write all the build scripts or package definitions - but they still have to do significant work in order to adapt them that everything fits together.
Or with Arch Linux, the packages are taken relatively vanilla from upstream, they package stuff more "as is" as compared to Debian. Which means less work, and often more clarity for experienced users.
Coming back to Void Linux, this means for these 100+ Void Linux packages which are currently orphaned, it is feasible that other people with good Linux experience adopt these, with a reasonable effort - some are important.