modify their individual utility functions into some compromise utility function, in a mutually verifiable way, or equivalently to jointly construct a successor AI with the same compromise utility function and then hand over control of resources to the successor AI
This is precisely equivalent to Coasean efficiency, FWIW—indeed, correspondence with some “compromise” welfare function is what it means for an outcome to be efficient in this sense. It’s definitely the case that humans, and agents more generally, can face obstacles to achieving this, so that they’re limited to some constrained-efficient outcome—something that does maximize some welfare function, but only after taking some inevitable constraints into account!
(For instance, if the pricing of some commodity, service or whatever is bounded due to an information problem, so that “cheap” versions of it predominate, then the marginal rates of transformation won’t necessarily be equalized across agents. Agent A might put her endowment towards goal X, while agent B will use her own resources to pursue some goal Y. But that’s a constraint that could in principle be well-defined—a transaction cost. Put them all together, and you’ll understand how these constraints determine what you lose to inefficiency—the “price of anarchy”, so to speak.)
It’s surprising to me that people are even debating whether mistake- or conflict-theory is the “correct” way of viewing politics. Conflict theory is always true ex ante, because the very definition of politics is the stuff that people might physically fight over, in the real world! You can’t get much more “conflict-theory” than that. Now of course, this is not to say that debate and deliberation might not also become important, and such practices do promote a “mistake-oriented” view of political processes. But that’s a means of de-escalation and creative problem solving, not some sort of proof that conflict is irrelevant to politics. Indeed, this is the whole reason why norms of fairness are taken to be especially important in politics, and in related areas such as law: a “fair” deliberation is generally successful at de-escalating conflict, in a way that a transparently “unfair” one (perhaps due to rampant elitism or over-intellectualism)-- even one that’s less “mistaken” in a broader sense—might not be.