This piece from one of the creators of ActivityPub is for me the definitive read on Bsky & its would-be decentralisation. A long text yes, but well worth the braintime.
Details and their devils, of particular interest is the practical infeasibility of self-hosted ATProto Relays, & also some of the threat modeling around investor heat on any push to re-architect toward true decentralisation.
Key lessons & directions for the Fedi are teased out alongside. Much greatness