Delete means to remove from database, no recovery
From a technical standpoint, this was not at all the case historically. By the time we moved from floppy disks to standard UNIX commands the presumption was that your data would be backed up and thus recoverable, and early RDBMs treated the equivalent to a DELETE SQL command the same way FAT did.
Nowhere in the English language semantically will you find that "delete" implies that you can recover it.
https://english.stackexchange.com/questions/518243/origin-of-the-word-delete
Delete as originally brought into English from Latin referred to smuding out in your wax slate, and later blotting out your writing to hide a mistake. In both ancient usages the mistake was potentially recoverable, a non-contradicting inference that continued on to the computer age.
Note that we don't generally say "delete" to mean "remove unrecoverably" in other contexts, either. The rules for handling classified material do not merely say "delete", but always compound it with qualifiers or expansive instructions such as "delete unrecoverably" or "delete files and backups".
As far as the hardware you are executing "delete" should follow that command.
Final point: the actions of a user with regard to their posts on Lemmy are not hardware commands. They are pure software concepts that interact with a distributed and abstracted system that is several steps removed from such.