But Signal is perfect to stay private against non-nation-state actors. If I want to make sure that my ISP, mobile carrier, etc. can't snoop on my messages, Signal is my phone messenger of choice. Until and unless Facebook is demonstrated to not be on the level regarding Whatsapp's implementation of the Signal protocol, then I'll keep Whatsapp on the list as well.
Telegram is not on that list. If my threat model consisted solely of "that guy with the manbun and macbook working on his novel in the coffeeshop", then maybe Telegram would be acceptable. Let me know when Telegram has default and mandatory end-to-end encryption, using a properly-implemented and proven-secure protocol like Signal's, on all clients both mobile and desktop. Until then I'll consider it to be about as secure as SMS - "hilariously not".