It depends what you understand by “cloud”. The example means just some kind of a 3rd party computer that you want to use to store and sync your files, but at the same time you don’t want anyone to be able to actually know what the files are. Hence, they are stored in a completely encrypted form, which covers their names too. This is not the same as when using Cryptomator and such, where you can still perform normal operations on the encrypted files.