[fooker]

'Random software' should not know anything about which file system your drive has. If it does (..say.. some kind of whole disk backup utility), and you are using an unexpected file system that is not really a problem in exFat.

[tinus_hn]

The details can easily leak, for instance with FAT in the limited resolution for timestamps or the case (in)sensitivity.

[Spivak]

Just a simple counterexample, SQLite is not supported on NFS. Applications are not as insulated from the underlying storage as you suggest.