Earlier quoted context omitted.
My only takeaway is that the "fediverse" is merely another layer/expression of centralization.
Decentralisation isn't perfect, and has its problems. That doesn't mean it's the same as centralisation.
Centralization is a network of peers all connected to one hub, reliant on the hub to provide spokes to other peers at large.
The "fediverse" as far as I can tell is a collection of many separate networks that refuse to speak with other networks (for ideological reasons at that, rather than technical), each network acting as a hub and providing spokes to their peers.
It's centralization ("Lemmy", et al.) within a centralization ("fediverse") within a decentralization (internet).