[motohagiography]

Even as a blockchain non-fan, those computations are necessary to produce the desirable thing, and the same could be said for protein folding. There are a lot of great and devastating criticisms of blockchains, but the environmental concern is more of a proxy or even dogwhistle for a general political objection to cryptocurrencies - even reasonable objections in the context of their worldview. Greenwashing those objections seems like a canard.

[squeaky-clean]

I think you two are disagreeing on what "the desirable thing" means. You're saying it's creating the bitcoin/blockchain which is the desirable result. But they're saying that "desirable result" here is actually just computing a SHA-256 below a certain threshold. Sure you get the blockchain as a result, but does it really need to be SHA-256? As long as you have a "hash" function with a statistically predictable amount of CPU usage to generate a "successful" result, that function could maybe be something more meaningful. I have no idea if you could quantify protein folding into some sort of statistically predictable successful/unsuccessful CPU process.