Don't assume blockchains are bitcoin or BTC like systems.
I talk about the "current and undisputed or better indisputable (final) state". Bitcoin does not have this. Hence it can not function without history. This is a property of BTC not one of blockchains in general.
Plenty other systems have a current state and a final state and there is no "better state" that can comer around and replace it. Final really means final. Its often called a closed ledger.
Other systems have checkpoints and what not to reach a similar goal.
BTCs "final" is just to wait some blocks its never final its just becomes incredibly unlikely to change the longer you wait. This is objectively worse than having a final state and on top of that it requires the history rather than just the last final state.
>Why should we trust a state created from thin air that has no proof of how it was created? That's just a distributed database, which has is uses, but it's not a distributed blockchain.
You have no choice. Either you agree with the current final state or you dont use the blockchain. Your choice is to use it or not. You choice is not to validate or not or validate and fix something if its wrong.
The act of validating doesn't do anything. No matter what your validating gives you in the end you can only accept the current final state of the running network or not use it at all.
Also its not created out of thin air. It was validated by the code. If there is a mistake it is there because of the code people used back when it happened. If you were there running your node it would have made the same mistake. whats the point to find it now? (beside the fact that it was already found and fixed) It doesn't change the state the state is final. Bugs happen.
If you assume cheating however then well you should assume someone would have screamed back when it happens so you would already know that someone cheated somehow. Whats the point of validating it? you already know you dont want to use that chain. Zero reason to detect the cheating yourself.
We know pretty well from all incidents where blockchains had to be "fixed" there is no way someone would find an unknown incident by the placebo validation act.