Comment by input_sh

I think we're definitely approaching time when Signal / WhatsApp / Facebook Messenger / Google Messages / Matrix / etc will all become at least somewhat interoperable, and it's gonna happen very fast (~Q3), mostly because EU's Digital Markets App is basically forcing them to. (Well okay, only Meta-owned platforms are forced to.)

Matrix did an interoperability talk on FOSDEM (https://fosdem.org/2024/schedule/event/fosdem-2024-3345-open...) and it's basically confirmed (https://www.wired.com/story/whatsapp-interoperability-messag...) there was some experimental work done on connecting WhatsApp (and ergo every other Signal protocol compatible app) and Matrix.