Ecosystems can sometimes "spend" decentralization at the wrong layer.

Decentralization with no centralization above (e.g. an hourglass shape) makes it harder to have innovation at the higher layers.

If there are multiple options at low layers it prevents innovation at upper layers where it might be more useful.

Go's go.dev is a great example.

You don't need to use go.dev at all--it has no special behaviors, it's just the obvious schelling point for the community to cohere around and it's great so why would you bother creating another one?