Telegram has E2E encryption, but only in Secret Chats: https://telegram.org/faq#secret-chats
You want secret chat for groups? Sorry, can't do. (Signal can.)
You want secret chats for desktop messages? Sorry, can't do. (Signal can.)
You want everything end-to-end encrypted by default? Sorry, can't do. (Signal. Can.)
You want secret chat for groups? Sorry, can't do. (Signal can.)
You want secret chats for desktop messages? Sorry, can't do. (Signal can.)
You want everything end-to-end encrypted by default? Sorry, can't do. (Signal. Can.)