the follow-up is also a great read
https://dustycloud.org/blog/re-re-bluesky-decentralization/
tldr;
bluesky is neither federating nor decentralized, but is a great twitter replacement (not that theres anything wrong with that)
e. also, the longer it exists, the less incentive they have for ever federating or decentralizing. so it will for, all intents and purposes, never do those things regardless of what the board that runs it professes.