bcachefs

Except this never happened :) I wrote an application that actually used distributed transactions with NTFS and SQL Server, for video file management from CCTV cameras, some time around 2008.

There were tons of corner cases that didn't work quite right. For example, if you created a folder and a file within that folder, then nobody else could create files in that folder until the transaction commits. Because the folder had to be deleted during the rollback.

And this at least made some sense within Windows, as it's a very lock-heavy system. It will make much less sense in a Linux FS.