That's not hindsight bias. Having a flood is Bayseian evidence in favor of the correct estimate of flooding having been high (and therefore in favor of negligence).
Yes, but it is hindsight bias to give that a lot of weight. (This is a common thing for lots of biases: they involve things which are strictly speaking actual Bayesian evidence but where humans frequently massively over-update based on them.)
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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