I strongly prefer that with XMPP I can disable the encryption when it breaks to tell my friend I'm trapped under a boulder and bleeding out. With Matrix our chat is encrypted, I can't turn it off ever, if it stops working I can't communicate, my only option is to make a new room with encryption disabled and invite my friend hoping he sees the invite and accepts in time.

That's how RCS's Universal Profile is too though as far as I understand with the new encryption standards.

Id rather someone be able to reach out to me with a note the chat is insecure, rather than be unreachable at all