the one thing that most federated platforms have over centralised structures is the possibility to migrate out of your current shitty fiefdom and the fact that the actual code is open source, so a community can make the choices about the possibilities the technology provides (which is mostly usually better than whatever a for profit company is “forced” into), whereas a centralised platform like bluesky can just ruin the codebase and keep it’s users hostage… which after all is one of the key factors to enshitification

edit: i do agree on your other points though, social networks are bound to turn into bubbles and we’ve already seen defederation based on petty squabbles :shrugs: