Recently, we changed the way that macOS installers (disk images) are created, so that there is no longer any need to drag a kicad folder into the /Library/Application Support/ folder. Instead, the files that were in this folder are now included inside the application bundle itself.
This means that administrator privileges are no longer required to install KiCad, and nor are the “hacks” that get around Apple’s desire to make it hard to modify these system folders.
If you have been running 5.99 nightlies, you may now delete the /Library/Application Support/kicad folder to free up disk space. Note that if you chose to import your library configuration from 5.99 when you first ran 6.0-rc1, your KiCad installation is probably still looking in this folder for the libraries, so if you delete it, you will no longer see your libraries. If you find yourself in this situation, you can fix it by deleting the configuration file ~/Library/Preferences/kicad/6.0/kicad_common.json.