Here you go: https://news.ycombinator.com/threads?id=autoexec&next=394457...

The paper you linked to was published before they started collecting and storing sensitive user data in the cloud

Here comes the evidence: https://news.ycombinator.com/item?id=39414322

In the spirit of CALEA, sealed sender basically pushes law enforcement back to good ol' days of "got the time", "got the IP addy", but "we don't know what was said".

> but "we don't know what was said

https://www.nybooks.com/online/2014/05/10/we-kill-people-bas...