@timbray Well you might be able to ''imagine'' a radically decentralised web without blockchain, but can you actually build one that's proof against inconsistencies from hostile participants?
If you can, write the white paper.
In one sense, the great social problem we face at the moment - fake news and the proliferation of conspiracy theories - are because the web is distributed but not proof against inconsistencies from hostile participants.
Obviously blockchain only solves this for the narrow domain of accountancy. But the fact that disinformation is now such a problem on other decentralised networks should cure us of the naivety of presuming we can ignore or muddle through the problem of bad actors on networks.
If a network is valuable at all, then this creates incentives for liars. Obviously for financial networks this is so self evident that we made protecting against lies the core idea of the network.
For most distributed networks we built, protection from liars has been secondary ...
And we now see the result.
So, sure, we need to get away from what's wasteful, particularly Proof of Work. Maybe even blockchains. Ideas like tangles are interesting.
But we can't have valuable new decentralised webs without thinking about problem of liars from the start.