I don’t know what I was expecting but it looks more and more like the Messaging Interoperability the EU promised will be each gatekeeper essentially publishing their client to server protocol and then you can either use multi protocol messengers or transports. No s2s federation.
Looks like one might be able to log in through the (propriety) c2s API with third party IDs though.
RE: https://gultsch.social/@daniel/111528938093114289
I knew pretty early that the EU regulation for IM interoperability is not going the way we want it to go. However the regulator is now looking at push services (FCM, APNS) and I believe we can make some real impact there. We have working solutions and our demands are significantly more actionable.