He went on to praise Signal, the encrypted chat app that is run as a non-profit. He said he had spoken with its creator, Moxie Marlinspike, who is now “potentially willing to help out” with encrypting Twitter DMs.

“Ironically, Moxie Marlinspike worked at Twitter and actually wanted to do encrypted DMs several years ago, [but] was denied that and then went and created Signal,” Musk said.

https://www.theverge.com/2022/11/21/23472174/twitter-dms-enc...