[vk23]

You are mixing things up. While it's true that Cryptocurrencies try to solve a different problem than BitTorrent, Git and Email neither of those applications rely on a single centralized server owned by a single company.

As for your question regarding practical purposes I think that a blockchain run by multiple banks or states can provide the same benefit for people as a fully decentralized system. I get that this is where censorship and control comes in but do you really want to live in a world where value can be moved around arbitrarily without regulation?

Also, while the blockchain itself is run decentralized the development is still somewhat centralized and most folks do not have the understanding or interest to investigate changes being made to the source that powers such blockchains.

[fastdev]

> You are mixing things up. While it's true that Cryptocurrencies try to solve a different problem than BitTorrent, Git and Email neither of those applications rely on a single centralized server owned by a single company.

I don't thing we disagree here. I am just pointing out that blockchain/Bitcoin/Ethereum is different because it allows to main a shared, verifiable state, something that BitTorrent, Git and Email do not provide. An ability to have this shared state is the main selling point of blockhain based systems.

[vk23]

I would argue that git at its core solves the problem of handling a shared verifiable state. The history of a git repository is build on the same hashing principles as a blockchain to ensure that history cannot be changed. The main difference to a blockchain is that in order to change the state you have to convince other humans that your change is valid.

In my understanding the main selling point of blockchains is to outsource the accepting of state changes to a consensus protocol which does not involve human interaction/interference. And just as git a blockchain still works if only one or few actors are involved.

[fastdev]

> In my understanding the main selling point of blockchains is to outsource the accepting of state changes to a consensus protocol which does not involve human interaction/interference. And just as git a blockchain still works if only one or few actors are involved.

Agree. git works for vaguely defined rules like "is this README readable, up to date, and useful" where human input is necessary.

Blockchains can be used to enforce clearly defined rules like rules of a smart contract or rules of spending virtual money.

So roughly speaking: git = blockchain - distributed_consensus + fork_merges