Meta built this under the Digital Markets Act (DMA), maintaining end-to-end encryption (E2EE) and some basic privacy guarantees. As a whole: you can talk across platforms without sacrificing security. (or WhatsApp's definition of it)
What messaging app would YOU want to see become interoperable with WhatsApp? Signal? Telegram? Matrix? Something else entirely?
Chat with the community about it:
https://discuss.techlore.tech/t/meta-messaging-interoperability-whatsapp-enables-third-party-chats-for-users-in-europe/15949
@mpanhans @techlore @xmpp well, the Problem with their "solution" is: everything still remains in the WhatsApp silo.
True interoperability would split the userbase onto different servers/providers and the huge pile of data WhatsApp is sitting on and their market power would shrink.
Of course the don't want that even if it would be good for society as a whole.