Many governments, including the US, are concerned right now that their computers have hardware backdoors, so the current lack of research results on this topic is not just due to lack of interest, but probably intrinsic difficulty. Even if provable hardware is physically possible and technically feasible in the future, there is likely a cost attached, for example running slower than non-provable hardware or using more resources.

Instead of confidently predicting that AIs will Cooperate in one-shot PD, wouldn't it be more reasonable to say that this is a possibility, which may or may not occur, depending on the feasibility and economics of various future technologies?