What does the word 'waste' mean to you? Why would you use this word to describe what is done by the proof of work?
If you think cryptocoins have no utility, then it stands to reason that the proof of work is wasteful. And beyond: the time and money spent by developers, corporations, exchanges, etc: all waste.
But if you think that cryptocoins do have some utility, then it seems unfair to call it a "proof-of-waste". The PoW is the only way to equitably mint new currency.
I thought it was implicit from context but I should have included "...[for a decentralized] currency."
I should have made it explicit that I meant "trustless + equitable" with respect to minting new currency.
> Why can't exchange of goods or services substitute for proof of work?
'exchange of goods or services' can't be used to mint new currency. When you want to issue new money, you have to give it to someone. If you take goods or services, who should get those? Let's say you come up with a method to solve that, equitably. How could you prove to everyone who got those, and how could they trust your claim?
> Why does proof of work _have_ to be power-hungry number crunching?
It might not have to be number crunching (I didn't say it did), it just happens to be the most popular. However I think that 'Work' here is the physics sense of the word -- the proof-of-work is evidence that you consumed energy.
Another mechanism is to just delete the "trustless" requirement. Just issue the currency via some trust-the-individual(s)-who-created-the-coin mechanism, like some DPoS coins do (e.g. Nano). They can use a fountain with a CAPTCHA, and we have to trust that the fountain is indeed fair. This coin is popular for the sake that it does not require PoW for minting and has no inflation.
If you concede that it has utility at all, then all you're saying is "I wouldn't be willing to pay that much". But clearly the market will bear a higher price than you're willing to pay.
Other things that are proof of waste: 1k USD iPhones, Cartoons on TV, all-you-care-to-eat restaurants, dabbing, hoverboards.
Not worth it to you. Just like your trip to Thailand is a waste of finite resources as far as I'm concerned. Who gets to decide, these things are subjective. That's why we use markets to allocate resources.
I understand that a central respository of work and the need to make the busywork scale cleanly and linearly makes it tough to be decentralized, but I regularly wish that a dominant cryptocurrency could find a way to do proof of (real) work with these cycles. There are so many projects which just lack for computing power (e.g. folding, prime hunting, etc), so it feels like even more of a waste to turning real power into arbitrary hashes.
If you think cryptocoins have no utility, then it stands to reason that the proof of work is wasteful. And beyond: the time and money spent by developers, corporations, exchanges, etc: all waste.
But if you think that cryptocoins do have some utility, then it seems unfair to call it a "proof-of-waste". The PoW is the only way to equitably mint new currency.