Finally, my Garden Linux PR feature(build): Add support for macOS #1013 got merged which allows building Garden Linux images on macOS regarding the underlying hardware architecture (Intel and Apple Silicon are supported). As a result, no further Linux virtual machines are needed to create artifacts. This is a big step forwards for all macOS users in usability and also speeds up the whole local build process.
Update: With PR Add support for macOS and CentOS (Stream) in startvm #1027 you may also directly run the created images on macOS.