Choosing Telegram over WhatsApp is a downgrade in terms of privacy: groups are not end-to-end encrypted and end-to-end encryption is opt-in on 1:1 chats. You need to trust them with your data.
With Signal, you don't, *everything* is e2e encrypted.
https://xiu.io/posts/10-whatsapp-what-now/
Le réseau social du BIM, fruit de la collaboration de 3 associations promouvant les Logiciels Libres et la Neutralité du net