Matrix servers that have it enabled (including QOTO's matrix server) allow for ephimerial rooms. That is, you can set your messages in a room to automatically delete after a certain point in time. Anyone who is the admin/mod of a room can set it. That, combined with the end-to-end encryption and identity verification really makes this a win on privacy.
Please let me know if anyone needs help.
If you want to sign up or log in you can go to: https://element.qoto.org
Everyone is welcome to signup, you dont need to have a QOTO account. You can also login as a guest if you wish.