Well, maybe we need to be more clear what we are trying to do: #deltachat apps are a cross-platform private messenger suite, that aims to provide a consistent UX/UI for users with lots of experience using WhatsApp and Signal.

Telegram has good fast UX but is hardly a private messenger (it has a central cleartext database of everyone and everything).

Matrix and XMPP are well-esteemed fellows in federated messaging, but so far didn't grow a WA/Signal-level cross-platform messaging UX.

YMMV