Fediverse/Mastodon meta
We can't even teach instances like picking an email provider because nobody chooses their email provider anymore. They're either in Gmail or they're on a company provided Microsoft Exchange or Google Apps domain.
Teaching federation requires a fundamental social change in the way we treat the internet, a damage caused by the last decade and a half of deep centralization of services. That's not Mastodon or the Fediverse's fault, but it inevitably impacts it.
Fediverse/Mastodon meta
Federation as a technology has been superceded by large corporations with enormous amounts of resources to throw at commoditized server space, but the social value of federation has not gone away, and somehow we have to re-teach that before we can really do anything else.