Distributed Press ( @distributed ) is drafting a new FEP for #ActivityPub for "Peer-to-peer Identities". The general gist is that objects (such as Actors and content) can link to alternate versions of themselves, which can be hosted elsewhere, such as #IPFS. If the server goes down, data can be served from there instead.

You can read the draft proposal here: https://codeberg.org/fediverse/fep/src/commit/3efef8bffd9581a116135be4953ccb2ebdf4f482/fep/1024/fep-1042.md