> Apologists will point to most crypto-mining using renewable energy. Yes, because hydro is the cheapest power. But all the hydro power use can actually limit the power and/or make it more expensive for everyone else.
As an admitted apologist, that's one of the weaker arguments. The most compelling to me is that power usage isn't properly compared to traditional banking. Sustaining all of the people and in person infrastructure required for traditional financial transactions requires more than just calculating the cost of transmitting the transaction. In fact those parts are comparatively cheap, it's the verification that's expensive, in both systems. All of the people employed in banks who play any kind of role have an enormous amount of cost associated with their employment. I'd like to see a comparison of heating and cooling costs for all of the banks in the world, which is just a small slice of the total cost of traditional banking, factored in to comparisons. The only one I've seen compared it to the computing cost for processing VISA transactions, which didn't seem like a proper comparison.
I'm also generally suspicious of some people (not everyone) who's gut instinct to environmental impact are limiting the spread of innovative and extremely useful ideas rather than looking at how to decrease the impact, particularly when those ideas help to decrease reliance on powerful central authorities. Proof of work is the innovation that allowed cryptocurrencies to scale to the level they are today, and it's precisely that work that allows them to operate securely despite being decentralized. Abandoning it because of the impact rather than reducing the impact would be like abandoning cars rather than making them electric and more efficient.
The focus is on transaction layer because that is what the crypto currencies provides. The blockchain doesn't run customer support, doesn't handle cash logistics, doesn't decide in conflicts involving the real world (e.g. if you do a blockchain escrow thing with multisig or smart contracts or whatever to give customers the equivalent of chargebacks in case of fraud, you still need humans to make the decision), ... so you can not just pretend all those human roles go away - and the people already working in blockchain ecosystems also aren't calculated against the blockchains in the calculations. Deciding which ones won't exist in the hypothetical all-blockchain world has far-reaching consequences, and probably something there is little consensus on. Proposals and estimations based on that would be interesting though.
Describing cryptocurrencies as a transaction layer does not describe the value. Communicating “Adam paid Bob X coins” is not hard.
What’s hard is having everyone agree on the same history of transactions. That’s what cryptocurrencies provide. There is an enormous amount of accounting and verification work that goes on within banking systems to solve the verification problem.
My argument was not that every human role has a cost that needs to be factored in, but that any human role has a high cost, and a large number of human roles require very large amounts of energy to support.
A fair bit of what you describe also can in fact be done with just smart contracts where the contract and those who sign it (the human customers) makes the decision without any middleman (without a human escrow agent).
As an admitted apologist, that's one of the weaker arguments. The most compelling to me is that power usage isn't properly compared to traditional banking. Sustaining all of the people and in person infrastructure required for traditional financial transactions requires more than just calculating the cost of transmitting the transaction. In fact those parts are comparatively cheap, it's the verification that's expensive, in both systems. All of the people employed in banks who play any kind of role have an enormous amount of cost associated with their employment. I'd like to see a comparison of heating and cooling costs for all of the banks in the world, which is just a small slice of the total cost of traditional banking, factored in to comparisons. The only one I've seen compared it to the computing cost for processing VISA transactions, which didn't seem like a proper comparison.
I'm also generally suspicious of some people (not everyone) who's gut instinct to environmental impact are limiting the spread of innovative and extremely useful ideas rather than looking at how to decrease the impact, particularly when those ideas help to decrease reliance on powerful central authorities. Proof of work is the innovation that allowed cryptocurrencies to scale to the level they are today, and it's precisely that work that allows them to operate securely despite being decentralized. Abandoning it because of the impact rather than reducing the impact would be like abandoning cars rather than making them electric and more efficient.