Without the value aspect of it, what would incentivize people to perform proof of work?
Work costs money: like electricity isn't free at the scale of the BTC Network. It costs thousands of dollars of electricity to run those BTC mining rigs to verify the ledger.
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If you're saying the future of "blockchains" is just a cryptographically signed ledger, without any proof of work or BTCs being assigned, I think I can agree with you on that.
But at the moment, "blockchain" is the new cloud. No one really knows what a "blockchain" is anymore, aside from a new electronic ledger of some kind. BTC is clearly a blockchain, but a lot of the "blockchain-based technologies" are nothing like BTC at all.
A lot of these "blockchains" are just centralized banks electronically verifying transactions. Like a notarized bill of sale, except the 'notarized' portion is electronic. Proof of work and all that stuff just don't exist in a lot of the "blockchain" solutions coming out.