As we've seen many times now immutability is not a strong property (indeed, none of the properties provided by blockchains are) of them, so not all that useful.

As we've seen many times now immutability is not a strong property (indeed, none of the properties provided by blockchains are) of them, so not all that useful. E.g. Ethereum's various hard forks to un-do things. In a manner of speaking, "history is written by the victors" applies to blockchains in more way than one (miners, orgs, hardforks, ...)