@youronlyone @atomicpoet @pablowapsi
This is all heavily retroactive categorization. Email isn't any more federated than phones or text messages. It's a working analogy for how posts are transfered here, but that's about it.
IRC was definitely not "federated", servers were just grouped into standalone networks. Sometimes.
XMPP sure, but that came out alongside AIM and MSN and was never that popular in comparison. Hardly a more federated, less branded past era of the Internet.