Let's forget about "fair" then, and focus on the allocation. Whether fair or not by someone's definition of "fair", the market system can allocate resources am

Let's forget about "fair" then, and focus on the allocation. Whether fair or not by someone's definition of "fair", the market system can allocate resources among uncountable federated actors, without spending a significant fraction of those resources on centralized calculations. A zero-price system cannot do that. There may exist theoretical alternate systems that can allocate more fairly than a market system. If one can do that with unmetered, no-additional-cost-to-the-consumer electricity, I'd be happy to hear about it, as I am not currently aware of any.