While the idea of data-deduplication does apply everywhere, this specifically depends on the APFS CoW data feature, so it's not applicable outside of macOS (or APFS Volumes)
but link is dangerous, as a edit made to one file will then be made to all copies.
For example, If I have two files /home/m/todo.txt and /home/m/backup2025/todo.txt that are identical and you then replace /home/m/todo.txt with a link to /home/m/backup2025/todo.txt and I later edit /home/m/todo.txt then backup copy would also be updated. With apfs clones the backup would not be modified when I updated the file.
