> "I can easily guess that assholes in secret service would probably like very much to use that to blackmail him to add backdoors to telegram. So sad."
Telegram is a backdoor by design. The server has complete access to all your messages, they can do whatever they want with those.
Goole Translate works good enough for this article, there is also one from "FiloSottile" but I haven't read it and iirc it still references this one, it's called "The most backdoor-looking bug I have ever seen"
Note that America has been caught spying on EU countries politicians and manufacturers so many times and nobody got ever punished for this. While the backdoor talks are purely hypothetical, and Telegram's client and protocol are open source: you can just study the code.
Telegram is a backdoor by design. The server has complete access to all your messages, they can do whatever they want with those.
And they even had a backdoor in E2EE chats, see: https://habr.com/ru/articles/206900/