Well, it's kind of a political question in a way, but I'd tend to focus on the goal of providing users the experiences they want and value, and that decentralized sharing of power can transfer power to users to help them reach their personal wants.
So you're missing the factor in the story that big social media platforms gave users experiences that they wanted, with different platforms giving experiences that different users wanted.
The experiences on Facebook and Twitter were VERY different, with users choosing to participate in one or the other or none based on their personal preferences.
The instance focus of Fediverse lets us add many new, potentially different experiences to help users find the one that best matches their individual wants.
And yep, that happens through distributing that power downwards.
