> If you ask a server to delete data, you have to trust it actually deletes it. That goes for any protocol; it's nothing to do with Matrix.

I've see this "critique" come up with multiple different protocols, and it's almost infuriating.

How does the protocol ensure the server removes the data in question from backups? How does the protocol handle someone copying the data off the server onto another device before deletion? How does the protocol handle servers that don't properly implement the data deletion portion of the protocol? How does the protocol handle wiping the neural synapses associated with the memory of that piece of data for each person who ever interacted with it? Without solving these problems, it seems to me the "delete" feature is nothing more than a suggestion, and therefor the protocol itself is fundamentally broken!!

Like, how do you take back something horrible you said to a friend? You don't. You fucking live with your mistake. Don't send shit to other people if you don't want them to, you know, have that information.