Last year Apple joined MS and Google in searching your hard drives and removable media with a background process that hashes all files looking for certain illegal images and video. But it's only a matter of a simple adjustment to add in naughty memes and pirated movies, shows, books, and music as well and hook that up to a system where either you're automatically reported or the files are deleted perhaps even silently.
Enjoy!
but all my shit's on external media!
It will be scanned when you mount or insert it.