I found it always fishy that telegram applauds itself for being a secure messenger but decided against encryption by default. With the flick of a switch every doubt would go away but alas.
Tribalism is a helluva drug.
(This is actually independent of you or Signal, I just find it amusing that people throw their security brand™ behind some app and it's just them picking the one they like most of the time.)
The 3-letter US agencies do not have direct access to Telegram's servers, they do have when it comes to Whatsapp (or to any other US-based company). The same goes if you're a Russian doing anti-government stuff in, well, Russia, it's better to put your fate in Whatsapp's (and Meta's) hands, presumably the US agencies won't come after you for being against the Russian government. It's a classical game of arbitration (for lack of a better word).
What makes you think so?