Thank you for your review. I have updated the script to mention running as the user with sudo.
Some people use the root user for administration.
shred_and_fill "$HOME/.local/share/Trash"
shred_and_fill "/root/.local/share/Trash"
If I, as a sysadmin give root rights to my user, and that user deletes my (real root) files, even from the Trash or anywhere else, then the next step includes such a level of violence that's not compatible with any kind of Code of Conduct.