We imagine a more capable site adapter running client-side and talking to many modern federation sites using a variety of protocols. We can't expect all federation clients to be so versatile so we look for some way for newer servers to help them out.
We already proxy http as https in some circumstances.
We can imagine github sites organized as status, pages and assets directories and explaining this to clients that can adapt themselves. But what about those that can't?
Retired sites could be bundled and transferred to a historical archive. We've seen some automatic backup to github work. Can we concoct a switch-over protocol?