Metadata that’s a holdover from the 1980s MacOS behavior. Hilariously, today, NTFS supports that metadata better than Apple’s own filesystems of today. They can hide it in Alternate Data Streams.
APFS still supports resource forks just fine - I can unstuff a 1990’s Mac application in Sequoia on a Apple Silicon Mac, copy it to my Synology NAS over SMB, and then access that NAS from a MacOS 9 Mac using AFP and it launches just fine.
The Finder just doesn’t use most of it so that it gets preserved in file copies and zip files and such.
Metadata that’s a holdover from the 1980s MacOS behavior. Hilariously, today, NTFS supports that metadata better than Apple’s own filesystems of today. They can hide it in Alternate Data Streams.
Why didn’t they add resource/data forks in APFS?
APFS still supports resource forks just fine - I can unstuff a 1990’s Mac application in Sequoia on a Apple Silicon Mac, copy it to my Synology NAS over SMB, and then access that NAS from a MacOS 9 Mac using AFP and it launches just fine.
The Finder just doesn’t use most of it so that it gets preserved in file copies and zip files and such.