And that might be better for accessing individual files outside the app instead of a big binary blob that you may have no clue on its format (or corruption/deletion of that single file). Thats why there are no universal solutions, there are many different use cases.
Nor does it let you start iterating through a directory with getdents(), then pause, then come back to iterate the rest of the files later. You have to receive every file name in the order the OS wants to give them to you.
That prevents applications really being able to make use of clever storage mechanisms - you can never find the most recent 3 files in a big directory with anything cheaper than a linear scan.
(But we have impressively speedy tools like Wiztree or Everything thanks to it.)
The most recent innovation for us is to use a lot of smaller SQLite databases, each scoped to a specific customer, session or unit of work. This is still far superior to loose records on disk, but you also get clear separation and reasonable firewalls between system entities.