@light Thank you.
However, I'd like to point out that only W3C ActivityPub is an elite protocol. The version of ActivityPub we use in Fediverse is a vernacular protocol (in @ntnsndr 's classification): early implementers picked parts of the spec that actually make sense and ignored C2S API and all the JSON-LD nonsense, making application development much more accessible. Today, Fediverse evolves rapidly through informal coordination and semi-formal processes like FEP, while W3C stuggles to fix a typo in the 8 years old specification.