Thinking about it I’m in an European country where Whatsapp is the default messenger app, if it had interoperability I could be on another FOSS app and be tracked by Meta just when I talk to people who are on Whatsapp and be free when talking to people not on Whatsapp, this could be great to make people switch “clients”, which is damn hard now because “everyone is on Whatsapp”. Interoperability is the shit and we should embrace it!