The internet is federated, but you don’t see tier 1 ISPs de-peering each other over arguments on social media.

No, but they intentionally cripple peering to blackmail others into paying extra or move their data-centers into the network of these bad-actor ISPs. Happens all the time sadly.

Email (which IS a great analogy… exactly because of the precedent for combatting abuse at scale) is federated, and you don’t see major providers blackholing major providers.

Keyword “major”. Everyone else is pretty much defederated these days, which is the point the article was trying to make.

Telephone networks and the banking system are both federated, and generally major players don’t de-peer other major players within established ecosystems.

Read up on history. You have this completely backwards. It took many years of government intervention to force them to open their networks. And in some countries banks still don’t interoperate or charge obscene rates for it.