[meltedcapacitor]

Facebook could also run federated technically, so that it never fails all at once. It failed because they put all the eggs in one basket in some top layer.

Technical decentralization is orthogonal to commercial issues.

[immibis]

If it was federated it wouldn't be Facebook, it would be Mastodon.

If it was federated and Facebook still controlled it, it would still be centralized.