VFSForGit is/was not a true file system, it just intercepts file I/O events to dummy files to lazily fill them with content and to log writes so that 'git status' does not have to scan the whole repo for changes.
The macOS port uses the KAUTH listener API, which was indeed deprecated with 10.15.
The macOS port uses the KAUTH listener API, which was indeed deprecated with 10.15.