Most mainstream sources right now are pushing Signal, claiming it has better encryption. Let's look at this claim, along with some other facts that have been modified or hidden from most of us.
So, given the facts above, why are most mainstream sources reporting that Telegram (a) doesn't have peer-to-eer (end-to-end) encryption; and/or (b) Telegram's encryption isn't as "good"? The short answer:
Signal's default (and only) mode is encrypted peer-to-peer, while Telegram's default is encrypted peer-to-server-to-peer, with an option for encrypted peer-to-peer, which Telegram calls "Secret Chat". Some sources either do not know this feature exists (always has) or they choose to ignore or misrepresent this fact. Maybe they just like the fact that Signal makes the decision for you and Telegram gives you too many pesky choices?
Why does Telegram even provide, peer-to-server-to-peer as an option? If you have played with both apps or looked at the comparison chart above, you may have noticed how many more features Telegram has.