Great point! My understanding is that proof of work is the only proven way to resist Sybil attacks in a fully distributed manner to-date. When someone invents

Great point! My understanding is that proof of work is the only proven way to resist Sybil attacks in a fully distributed manner to-date. When someone invents a better mechanism they will certainly have a huge economic advantage if you can join and support the miner network without consuming so many real resources. Decentralized Sybil resistance at this point requires a hard cost to limit spam. In a fully decentralized system, this seems like a natural law that this must be true. I have ideas on how to solve Sybil without resource exhaustion, but they are just at the initial prototype phase. If the critique is that Bitcoin specifically isn’t worth the “cost” of all the electricity, it’s a moral question which is easily solved by better pricing electricity. If the critique is Bitcoin is wasteful, then point to a more efficient algorithm or it’s tilting at windmills. There are algorithms which aren’t as resource intensive but the market judged the trade-offs in centralization to not be worth the benefits. We’ve know how to store a centralized ledger for a long time, so it’s totally reasonable that steps towards centralization for efficiency sake are a non-starter.