I am not open to your ahistorical take on Google Chat and XMPP.

Google didn't do anything wrong by using an open standard.

They didn't do anything wrong by building a good interface that people liked to use.

And they didn't do anything wrong by disconnecting from the network when the spam and harassment outweighed the benefit to their users.

We, the XMPP community, failed to capitalize on success by diversifying the network. It's our own fault not enough nodes were there.

If you'd like to draw some conclusions about ActivityPub from this, it should not be that a network should disallow supernodes, but that we have to counterbalance them with a wide diversity of other nodes of different sizes with different value propositions.
That huge audience of GChat users was an immense asset, and we fumbled it.
Note for my subtooter: there's not a recipe for this. Sometimes a group of independent Open Source developers and advocates manage to change the world. Other times, they don't. I think one big success factor is having people whose full-time job is expanding the network and making it healthy, unrelated to their own node or implementation. But not always. If I knew how it works and could replicate it consistently, the Internet would be a lot different.

@evan

What makes any network “work” or not is a balance of features and humans.

I am amazed that all the new apps or platforms [threads] are not taking the time to be more creative and sociotechnical about the features with a recognition to NOT recreate the past. Whether fediverse or owned.