Also take the "can't see your messages" statement with a grain of salt. Like the famous Lotus Notes backdoor [1] they might have given the government an easy(ier) way to decrypt those messages.
The backdoor in Lotus Notes (differential cryptography) wasn't a secret. It was public information. Ray Ozzie used it as a way to circumvent US encryption export laws. Today companies have to be more discrete.
https://transparency.meta.com/reports/government-data-reques...
They can't see your messages but then can give ips or accounts that can be inferred to be related given the info meta has access to