You suggest IPFS, but isn’t that what web3 is?

Web3 is blockchain + IPFS and/or torrents or whatever p2p protocol.

I am not suggesting storing the data itself on the blockchain, but the index, the equivalent of simple HTML pages on the blockchain so we never lose track of the data we share with torrents or whatever peer to peer protocol.

However, if it became used in the majority for censorship resistant data sharing, and transactions were the minority, I doubt that this would stop authorities going after node operators and so on.

I doubt it would exceed transactions, but if it did, authorities would need a global agreement with every single nation to take down all nodes, and that is never happening.

The problem of curating data and deciding what is worth archiving, and what is a true-to-source archive vs fake copy. This probably requires either a centralised trusted party, or maybe a voting system

I agree with you on this, but a voting system doesn’t sound too difficult to implement. And alternatively the internet archive could be that centralized trusted party. Arresting them for reporting on what data is correct would surely be unconstitutional.