Wii Backup Manager is described as 'program to work with DVD backups, FAT32, NTFS and WBFS drives to convert between DVD, ISO, CISO and WBFS. It can also extract Wii games to the format used by SNEEK' and is an app in the File Management category. There are four alternatives to Wii Backup Manager for Linux, Mac and Windows. The best alternative is Witgui, which is free. Other great apps like Wii Backup Manager are jwbfs (Free, Open Source), WBFS Manager (Free, Open Source) and Wiithon (Free, Open Source).
Witgui is a free Wii and GameCube game manager for macOS. It is a graphical user interface based on wit (http://wit.wiimm.de/wit), wwt (http://wit.wiimm.de/wwt) and the gametdb.com database. You will love its intuitiveness.