Satoshi Nakamoto’s Bitcoin blockchain addressed the problem of money existing in two places at once.
This Byzantine Generals problem had never been solved before… Now you could transfer digital assets to someone else, and the transaction was recorded forever.
No need for a third party. The consensus was that a particular trade was agreed to and it was recorded on the blockchain as permanent.
It was immutable… The concept was simple.
But beyond voluntary two party Bitcoin transactions there are probably very few analogous uses where immutable permanence is needed, or even advisable.
Along with opinions, positions, errors and mistakes, certain things were just meant to be reconsidered and changed.