It's called flat file storage and it has a number of advantages and disadvantages. I prefer it because it is more robust and performs well, even for large amoun

It's called flat file storage and it has a number of advantages and disadvantages. I prefer it because it is more robust and performs well, even for large amounts of data, as long as your filesystem is reasonably fast and reliable. Think maildir vs. mbox/PST/etc. for message storage. I stopped counting the number of times that I have seen Outlook mangle its message database and require a rebuild. Generally it is not so popular, in part because of the OSes like Windows and macOS which have somewhat lacking filesystem implementations. Git also has performance issues with large repositories on Windows, which need to be worked around by various methods. Transactions are another limitation as mentioned by the other reply (they are possible to implement on top of "normal" filesystems, but not in a portable way).