I was struggling to wrap my head around how federated social media works until I realized that email has basically been doing the same thing for 30 years. Different email servers are like instances of a federated network. You can send emails to people from within a single server or you can send emails to people on any other mail server. Your email address is a username followed by an ‘@’ and the server address, just like on Lemmy. Email is a decentralized service I’ve been using the whole time!
Not sure how anyone can say “GPG” and “Works great” in the same sentence tbh. GPG is a usability nightmare except for the most advanced users who use it. Good luck trying to get your house contractor or doctor or representative or non-techie friends and family or really anyone to give you their “public key”