Why do they have the data in the first place?
Your communications on telegram are not encrypted by default. You can have e2e encrypted 1on1-conversations, but group chats are blown for them to do everything.
They had a hilarious argumentation where they claimed that the key to unlock your chats is stored on a different server than your chats are and therefore they cannot access it. A company that argues like they (“trust us”) isn’t trustworthy.
Signal has been audited over and over again by internationally respected cryptographers. They cannot decrypt your chats by design. No need for “trust us bro”.
“Meteor” by Dan Brown (could be a different name in the original language). It was the first time I read something that was bad. Up until then book were cool and fun and interesting. It was a puzzling experience.
Edit: it’s called “Deception Point” in the original.