Yep, agreed. I was thinking primarily of targeting in the sense of using my landscape/hobby shots for commercial gain rather than personal photos including people when I was talking about my photography. But even then, I suppose it does make sense to encrypt anything that’s destined for storage out of one’s control and be done with it.
Using duplicity even on large collections of data may not be that slow actually; I know it keeps meta information locally so it may be able to quickly work out which files need re-encrypting based on checksums before it starts the process.