TLDR; Let’s make a framework for protocols that introduces the notion of ‘user’ and handles federation and user device connectivity.
If I were to become an all powerful god who could dictate all and any decisions made, we would have instant messaging. Not Signal, WhatsApp, Facebook Messenger, iMessage or even Matrix, but only instant messaging. When you would want someone’s contact, you would ask only for their address. And to buy them a coffee, you wouldn’t be asking if they have Bitcoin or PayPal or Revolut or N26, but you would only ask for their address.
I personally don’t like the idea, because keeping services entirely disconnected is good for privacy.
Furthermore, I think it’s funny that the author used Matrix as an example of a service benefiting from chat federation, when Matrix is about to be deportalled from Libera.Chat due to bad UX and leaking secret channels. If Matrix can’t even federate properly with IRC, there’s no way they can do it with modern services like Discord.