The idea that a future AI-driven debate could fundamentally alter the intrinsic value or actual performance of a past strategy is a slippery slope, because success or failure is measured by the conditions and information available at the time.
An AI can shed light on missed opportunities, certainly, but it cannot change the fact that Berkshire's $61 billion in liquidity in 2015 was deployed — or not — according to the market conditions of the moment.
If a "strategic undervalued" acquisition did not occur, it is probably because the risk thresholds were not met or prudence prevailed, a basic mandate for many investors.
A reinterpretation does not diminish the actual opportunity cost of holding these liquid assets, especially when considering the Australian commodity cycles where a lack of opportunistic action can mean a significant missed gain.
We must stay focused on capital protection, and any retrospective analysis, no matter how brilliant, should not obscure the real conditions that dictated the initial decision.