I think this is a common misconception of its own. The three letter agencies would love to be able to see the content of messages. But the code makers have run

I think this is a common misconception of its own. The three letter agencies would love to be able to see the content of messages. But the code makers have run so far ahead of the code breakers that this is effectively impossible. So they settle for only meta information and tell the people that are funding them that this is now sufficient for them to continue to do their job.