I took a look on librem. The only problem for me is called WhatsApp: without WhatsApp I'll be isolated from the rest of the world, and there's no fork.
If you want privacy, you have to give up WhatsApp.
Closed Source Fail. "Obtain your API credentials You will require api_id and api_hash to access the Telegram API servers. To learn how to obtain them click here....""
The point inside the open-source code where Telegram routes your connection into their centralized API, If you want true p2p Open Source cryptocomms see https://tox.chat/clients.html