Telegram's founder Pavel Durov says his company only employs around 30 engineers. Security experts say that raises serious questions about the company's cybersecurity.
The regular chats are encrypted though, just with an (encrypted) server in the middle. Telegram also claims in their FAQ, that no one singular person has the power to decrypt and the keys are stored such that no singular government could force them to give up any data.
How far that is true is a different question though.
What if its not e2e encrypted if they dont care. I know a bunch of chatrooms where you can watch paid movies that was released recently for free and Telegram dont care