No? I am asking for web app storage that I can point syncthing/dropbox to... or backup to my server.. or open in alternative client which is written in a differ

No? I am asking for web app storage that I can point syncthing/dropbox to... or backup to my server.. or open in alternative client which is written in a different language... or parse with ad-hoc Python script... You know, something that was forever possible with every application which uses OS's file system.